un rompicapo crittotmetico è un esercizio matematico in cui le cifre di alcuni numeri sono rappresentate da lettere (o simboli). Ogni lettera rappresenta una cifra univoca. L'obiettivo è trovare le cifre in modo da verificare una determinata equazione matematica:
CP + IS + FUN -------- = TRUE
Un'assegnazione di lettere alle cifre produce la seguente equazione:
23 + 74 + 968 -------- = 1065
Esistono altre risposte a questo problema. Ti mostreremo come trovare tutte le soluzioni.
Modellazione del problema
Come per qualsiasi problema di ottimizzazione, inizieremo identificando variabili e vincoli. Le variabili sono le lettere, che possono assumere qualsiasi valore a una sola cifra.
Per CP + IS + FUN = TRUE, i vincoli sono i seguenti:
- L'equazione:
CP + IS + FUN = TRUE
. - Ciascuna delle dieci lettere deve essere una cifra diversa.
C
,I
,F
eT
non possono essere zero (poiché non scriviamo zero iniziali nei numeri).
Puoi risolvere problemi di crittotmetica con il nuovo risolutore CP-SAT, più efficiente, o con il risolutore CP originale. Ti mostreremo esempi che utilizzano entrambi i risolutori, a partire da CP-SAT.
Soluzione CP-SAT
Mostreremo le variabili, i vincoli, la chiamata del risolutore e infine i programmi completi.
Importa le librerie
Il seguente codice importa la libreria richiesta.
Python
from ortools.sat.python import cp_model
C++
#include <stdlib.h> #include <cstdint> #include "ortools/base/logging.h" #include "ortools/sat/cp_model.h" #include "ortools/sat/cp_model.pb.h" #include "ortools/sat/cp_model_solver.h" #include "ortools/sat/model.h" #include "ortools/sat/sat_parameters.pb.h" #include "ortools/util/sorted_interval_list.h"
Java
import com.google.ortools.Loader; import com.google.ortools.sat.CpModel; import com.google.ortools.sat.CpSolver; import com.google.ortools.sat.CpSolverSolutionCallback; import com.google.ortools.sat.IntVar; import com.google.ortools.sat.LinearExpr;
C#
using System; using Google.OrTools.Sat;
Dichiara il modello
Il codice seguente dichiara il modello per il problema.
Python
model = cp_model.CpModel()
C++
CpModelBuilder cp_model;
Java
CpModel model = new CpModel();
C#
CpModel model = new CpModel(); int kBase = 10; IntVar c = model.NewIntVar(1, kBase - 1, "C"); IntVar p = model.NewIntVar(0, kBase - 1, "P"); IntVar i = model.NewIntVar(1, kBase - 1, "I"); IntVar s = model.NewIntVar(0, kBase - 1, "S"); IntVar f = model.NewIntVar(1, kBase - 1, "F"); IntVar u = model.NewIntVar(0, kBase - 1, "U"); IntVar n = model.NewIntVar(0, kBase - 1, "N"); IntVar t = model.NewIntVar(1, kBase - 1, "T"); IntVar r = model.NewIntVar(0, kBase - 1, "R"); IntVar e = model.NewIntVar(0, kBase - 1, "E"); // We need to group variables in a list to use the constraint AllDifferent. IntVar[] letters = new IntVar[] { c, p, i, s, f, u, n, t, r, e }; // Define constraints. model.AddAllDifferent(letters); // CP + IS + FUN = TRUE model.Add(c * kBase + p + i * kBase + s + f * kBase * kBase + u * kBase + n == t * kBase * kBase * kBase + r * kBase * kBase + u * kBase + e); // Creates a solver and solves the model. CpSolver solver = new CpSolver(); VarArraySolutionPrinter cb = new VarArraySolutionPrinter(letters); // Search for all solutions. solver.StringParameters = "enumerate_all_solutions:true"; // And solve. solver.Solve(model, cb); Console.WriteLine("Statistics"); Console.WriteLine($" conflicts : {solver.NumConflicts()}"); Console.WriteLine($" branches : {solver.NumBranches()}"); Console.WriteLine($" wall time : {solver.WallTime()} s"); Console.WriteLine($" number of solutions found: {cb.SolutionCount()}"); } }
Definizione delle variabili
Quando utilizzi il risolutore CP-SAT, è utile definire alcuni metodi helper.
Utilizzeremo NewIntVar
, per dichiarare le nostre cifre (numero intero).
Distinguiamo tra le lettere che possono potenzialmente essere zero e quelle che
non possono farlo (C
, I
, F
e T
).
Python
base = 10 c = model.new_int_var(1, base - 1, "C") p = model.new_int_var(0, base - 1, "P") i = model.new_int_var(1, base - 1, "I") s = model.new_int_var(0, base - 1, "S") f = model.new_int_var(1, base - 1, "F") u = model.new_int_var(0, base - 1, "U") n = model.new_int_var(0, base - 1, "N") t = model.new_int_var(1, base - 1, "T") r = model.new_int_var(0, base - 1, "R") e = model.new_int_var(0, base - 1, "E") # We need to group variables in a list to use the constraint AllDifferent. letters = [c, p, i, s, f, u, n, t, r, e] # Verify that we have enough digits. assert base >= len(letters)
C++
const int64_t kBase = 10; // Define decision variables. Domain digit(0, kBase - 1); Domain non_zero_digit(1, kBase - 1); IntVar c = cp_model.NewIntVar(non_zero_digit).WithName("C"); IntVar p = cp_model.NewIntVar(digit).WithName("P"); IntVar i = cp_model.NewIntVar(non_zero_digit).WithName("I"); IntVar s = cp_model.NewIntVar(digit).WithName("S"); IntVar f = cp_model.NewIntVar(non_zero_digit).WithName("F"); IntVar u = cp_model.NewIntVar(digit).WithName("U"); IntVar n = cp_model.NewIntVar(digit).WithName("N"); IntVar t = cp_model.NewIntVar(non_zero_digit).WithName("T"); IntVar r = cp_model.NewIntVar(digit).WithName("R"); IntVar e = cp_model.NewIntVar(digit).WithName("E");
Java
int base = 10; IntVar c = model.newIntVar(1, base - 1, "C"); IntVar p = model.newIntVar(0, base - 1, "P"); IntVar i = model.newIntVar(1, base - 1, "I"); IntVar s = model.newIntVar(0, base - 1, "S"); IntVar f = model.newIntVar(1, base - 1, "F"); IntVar u = model.newIntVar(0, base - 1, "U"); IntVar n = model.newIntVar(0, base - 1, "N"); IntVar t = model.newIntVar(1, base - 1, "T"); IntVar r = model.newIntVar(0, base - 1, "R"); IntVar e = model.newIntVar(0, base - 1, "E"); // We need to group variables in a list to use the constraint AllDifferent. IntVar[] letters = new IntVar[] {c, p, i, s, f, u, n, t, r, e};
C#
int kBase = 10; IntVar c = model.NewIntVar(1, kBase - 1, "C"); IntVar p = model.NewIntVar(0, kBase - 1, "P"); IntVar i = model.NewIntVar(1, kBase - 1, "I"); IntVar s = model.NewIntVar(0, kBase - 1, "S"); IntVar f = model.NewIntVar(1, kBase - 1, "F"); IntVar u = model.NewIntVar(0, kBase - 1, "U"); IntVar n = model.NewIntVar(0, kBase - 1, "N"); IntVar t = model.NewIntVar(1, kBase - 1, "T"); IntVar r = model.NewIntVar(0, kBase - 1, "R"); IntVar e = model.NewIntVar(0, kBase - 1, "E"); // We need to group variables in a list to use the constraint AllDifferent. IntVar[] letters = new IntVar[] { c, p, i, s, f, u, n, t, r, e };
Definizione dei vincoli
Passiamo ora ai vincoli. Innanzitutto, ci assicuriamo che tutte le lettere abbiano valori diversi,
utilizzando il metodo helper AddAllDifferent
. Quindi usiamo il metodo helper AddEquality
per creare vincoli che applichino l'uguaglianza di CP + IS + FUN = TRUE
.
Python
model.add_all_different(letters) # CP + IS + FUN = TRUE model.add( c * base + p + i * base + s + f * base * base + u * base + n == t * base * base * base + r * base * base + u * base + e )
C++
// Define constraints. cp_model.AddAllDifferent({c, p, i, s, f, u, n, t, r, e}); // CP + IS + FUN = TRUE cp_model.AddEquality( c * kBase + p + i * kBase + s + f * kBase * kBase + u * kBase + n, kBase * kBase * kBase * t + kBase * kBase * r + kBase * u + e);
Java
model.addAllDifferent(letters); // CP + IS + FUN = TRUE model.addEquality(LinearExpr.weightedSum(new IntVar[] {c, p, i, s, f, u, n, t, r, u, e}, new long[] {base, 1, base, 1, base * base, base, 1, -base * base * base, -base * base, -base, -1}), 0);
C#
// Define constraints. model.AddAllDifferent(letters); // CP + IS + FUN = TRUE model.Add(c * kBase + p + i * kBase + s + f * kBase * kBase + u * kBase + n == t * kBase * kBase * kBase + r * kBase * kBase + u * kBase + e);
Stampante di soluzioni
Di seguito è mostrato il codice della stampante della soluzione, che mostra ogni soluzione man mano che il risolutore la trova.
Python
class VarArraySolutionPrinter(cp_model.CpSolverSolutionCallback): """Print intermediate solutions.""" def __init__(self, variables: list[cp_model.IntVar]): cp_model.CpSolverSolutionCallback.__init__(self) self.__variables = variables self.__solution_count = 0 def on_solution_callback(self) -> None: self.__solution_count += 1 for v in self.__variables: print(f"{v}={self.value(v)}", end=" ") print() @property def solution_count(self) -> int: return self.__solution_count
C++
Model model; int num_solutions = 0; model.Add(NewFeasibleSolutionObserver([&](const CpSolverResponse& response) { LOG(INFO) << "Solution " << num_solutions; LOG(INFO) << "C=" << SolutionIntegerValue(response, c) << " " << "P=" << SolutionIntegerValue(response, p) << " " << "I=" << SolutionIntegerValue(response, i) << " " << "S=" << SolutionIntegerValue(response, s) << " " << "F=" << SolutionIntegerValue(response, f) << " " << "U=" << SolutionIntegerValue(response, u) << " " << "N=" << SolutionIntegerValue(response, n) << " " << "T=" << SolutionIntegerValue(response, t) << " " << "R=" << SolutionIntegerValue(response, r) << " " << "E=" << SolutionIntegerValue(response, e); num_solutions++; }));
Java
static class VarArraySolutionPrinter extends CpSolverSolutionCallback { public VarArraySolutionPrinter(IntVar[] variables) { variableArray = variables; } @Override public void onSolutionCallback() { for (IntVar v : variableArray) { System.out.printf(" %s = %d", v.getName(), value(v)); } System.out.println(); solutionCount++; } public int getSolutionCount() { return solutionCount; } private int solutionCount; private final IntVar[] variableArray; }
C#
public class VarArraySolutionPrinter : CpSolverSolutionCallback { public VarArraySolutionPrinter(IntVar[] variables) { variables_ = variables; } public override void OnSolutionCallback() { { foreach (IntVar v in variables_) { Console.Write(String.Format(" {0}={1}", v.ToString(), Value(v))); } Console.WriteLine(); solution_count_++; } } public int SolutionCount() { return solution_count_; } private int solution_count_; private IntVar[] variables_; }
Richiamo del risolutore
Infine risolviamo il problema e mostriamo la soluzione. Il metodo operations_research::sat::SolveCpModel()
sta tutto al grande.
Python
solver = cp_model.CpSolver() solution_printer = VarArraySolutionPrinter(letters) # Enumerate all solutions. solver.parameters.enumerate_all_solutions = True # Solve. status = solver.solve(model, solution_printer)
C++
// Tell the solver to enumerate all solutions. SatParameters parameters; parameters.set_enumerate_all_solutions(true); model.Add(NewSatParameters(parameters)); const CpSolverResponse response = SolveCpModel(cp_model.Build(), &model); LOG(INFO) << "Number of solutions found: " << num_solutions;
Java
CpSolver solver = new CpSolver(); VarArraySolutionPrinter cb = new VarArraySolutionPrinter(letters); // Tell the solver to enumerate all solutions. solver.getParameters().setEnumerateAllSolutions(true); // And solve. solver.solve(model, cb);
C#
// Creates a solver and solves the model. CpSolver solver = new CpSolver(); VarArraySolutionPrinter cb = new VarArraySolutionPrinter(letters); // Search for all solutions. solver.StringParameters = "enumerate_all_solutions:true"; // And solve. solver.Solve(model, cb);
Quando esegui il programma, viene visualizzato il seguente output, in cui ogni riga rappresenta una soluzione:
C=2 P=3 I=7 S=4 F=9 U=6 N=8 T=1 R=0 E=5 C=2 P=4 I=7 S=3 F=9 U=6 N=8 T=1 R=0 E=5 C=2 P=5 I=7 S=3 F=9 U=4 N=8 T=1 R=0 E=6 C=2 P=8 I=7 S=3 F=9 U=4 N=5 T=1 R=0 E=6 C=2 P=8 I=7 S=3 F=9 U=6 N=4 T=1 R=0 E=5 C=3 P=7 I=6 S=2 F=9 U=8 N=5 T=1 R=0 E=4 C=6 P=7 I=3 S=2 F=9 U=8 N=5 T=1 R=0 E=4 C=6 P=5 I=3 S=2 F=9 U=8 N=7 T=1 R=0 E=4 C=3 P=5 I=6 S=2 F=9 U=8 N=7 T=1 R=0 E=4 C=3 P=8 I=6 S=4 F=9 U=2 N=5 T=1 R=0 E=7 C=3 P=7 I=6 S=5 F=9 U=8 N=2 T=1 R=0 E=4 C=3 P=8 I=6 S=5 F=9 U=2 N=4 T=1 R=0 E=7 C=3 P=5 I=6 S=4 F=9 U=2 N=8 T=1 R=0 E=7 C=3 P=4 I=6 S=5 F=9 U=2 N=8 T=1 R=0 E=7 C=3 P=2 I=6 S=5 F=9 U=8 N=7 T=1 R=0 E=4 C=3 P=4 I=6 S=8 F=9 U=2 N=5 T=1 R=0 E=7 C=3 P=2 I=6 S=7 F=9 U=8 N=5 T=1 R=0 E=4 C=3 P=5 I=6 S=8 F=9 U=2 N=4 T=1 R=0 E=7 C=3 P=5 I=6 S=7 F=9 U=8 N=2 T=1 R=0 E=4 C=2 P=5 I=7 S=6 F=9 U=8 N=3 T=1 R=0 E=4 C=2 P=5 I=7 S=8 F=9 U=4 N=3 T=1 R=0 E=6 C=2 P=6 I=7 S=5 F=9 U=8 N=3 T=1 R=0 E=4 C=2 P=4 I=7 S=8 F=9 U=6 N=3 T=1 R=0 E=5 C=2 P=3 I=7 S=8 F=9 U=6 N=4 T=1 R=0 E=5 C=2 P=8 I=7 S=5 F=9 U=4 N=3 T=1 R=0 E=6 C=2 P=8 I=7 S=4 F=9 U=6 N=3 T=1 R=0 E=5 C=2 P=6 I=7 S=3 F=9 U=8 N=5 T=1 R=0 E=4 C=2 P=5 I=7 S=3 F=9 U=8 N=6 T=1 R=0 E=4 C=2 P=3 I=7 S=5 F=9 U=4 N=8 T=1 R=0 E=6 C=2 P=3 I=7 S=5 F=9 U=8 N=6 T=1 R=0 E=4 C=2 P=3 I=7 S=6 F=9 U=8 N=5 T=1 R=0 E=4 C=2 P=3 I=7 S=8 F=9 U=4 N=5 T=1 R=0 E=6 C=4 P=3 I=5 S=8 F=9 U=2 N=6 T=1 R=0 E=7 C=5 P=3 I=4 S=8 F=9 U=2 N=6 T=1 R=0 E=7 C=6 P=2 I=3 S=7 F=9 U=8 N=5 T=1 R=0 E=4 C=7 P=3 I=2 S=6 F=9 U=8 N=5 T=1 R=0 E=4 C=7 P=3 I=2 S=8 F=9 U=4 N=5 T=1 R=0 E=6 C=6 P=4 I=3 S=8 F=9 U=2 N=5 T=1 R=0 E=7 C=5 P=3 I=4 S=6 F=9 U=2 N=8 T=1 R=0 E=7 C=4 P=3 I=5 S=6 F=9 U=2 N=8 T=1 R=0 E=7 C=5 P=6 I=4 S=3 F=9 U=2 N=8 T=1 R=0 E=7 C=7 P=4 I=2 S=3 F=9 U=6 N=8 T=1 R=0 E=5 C=7 P=3 I=2 S=4 F=9 U=6 N=8 T=1 R=0 E=5 C=6 P=2 I=3 S=5 F=9 U=8 N=7 T=1 R=0 E=4 C=7 P=3 I=2 S=5 F=9 U=4 N=8 T=1 R=0 E=6 C=6 P=4 I=3 S=5 F=9 U=2 N=8 T=1 R=0 E=7 C=6 P=5 I=3 S=4 F=9 U=2 N=8 T=1 R=0 E=7 C=7 P=5 I=2 S=3 F=9 U=4 N=8 T=1 R=0 E=6 C=4 P=6 I=5 S=3 F=9 U=2 N=8 T=1 R=0 E=7 C=6 P=5 I=3 S=8 F=9 U=2 N=4 T=1 R=0 E=7 C=6 P=5 I=3 S=7 F=9 U=8 N=2 T=1 R=0 E=4 C=7 P=5 I=2 S=8 F=9 U=4 N=3 T=1 R=0 E=6 C=7 P=5 I=2 S=6 F=9 U=8 N=3 T=1 R=0 E=4 C=5 P=8 I=4 S=6 F=9 U=2 N=3 T=1 R=0 E=7 C=4 P=8 I=5 S=6 F=9 U=2 N=3 T=1 R=0 E=7 C=4 P=8 I=5 S=3 F=9 U=2 N=6 T=1 R=0 E=7 C=5 P=8 I=4 S=3 F=9 U=2 N=6 T=1 R=0 E=7 C=7 P=8 I=2 S=3 F=9 U=4 N=5 T=1 R=0 E=6 C=7 P=8 I=2 S=3 F=9 U=6 N=4 T=1 R=0 E=5 C=7 P=8 I=2 S=4 F=9 U=6 N=3 T=1 R=0 E=5 C=7 P=8 I=2 S=5 F=9 U=4 N=3 T=1 R=0 E=6 C=6 P=8 I=3 S=5 F=9 U=2 N=4 T=1 R=0 E=7 C=6 P=8 I=3 S=4 F=9 U=2 N=5 T=1 R=0 E=7 C=6 P=7 I=3 S=5 F=9 U=8 N=2 T=1 R=0 E=4 C=7 P=6 I=2 S=5 F=9 U=8 N=3 T=1 R=0 E=4 C=7 P=3 I=2 S=5 F=9 U=8 N=6 T=1 R=0 E=4 C=7 P=4 I=2 S=8 F=9 U=6 N=3 T=1 R=0 E=5 C=7 P=3 I=2 S=8 F=9 U=6 N=4 T=1 R=0 E=5 C=5 P=6 I=4 S=8 F=9 U=2 N=3 T=1 R=0 E=7 C=4 P=6 I=5 S=8 F=9 U=2 N=3 T=1 R=0 E=7 C=7 P=6 I=2 S=3 F=9 U=8 N=5 T=1 R=0 E=4 C=7 P=5 I=2 S=3 F=9 U=8 N=6 T=1 R=0 E=4 Statistics - status : OPTIMAL - conflicts : 110 - branches : 435 - wall time : 0.014934 ms - solutions found : 72
Completa i programmi
Ecco i programmi completi.
Python
"""Cryptarithmetic puzzle. First attempt to solve equation CP + IS + FUN = TRUE where each letter represents a unique digit. This problem has 72 different solutions in base 10. """ from ortools.sat.python import cp_model class VarArraySolutionPrinter(cp_model.CpSolverSolutionCallback): """Print intermediate solutions.""" def __init__(self, variables: list[cp_model.IntVar]): cp_model.CpSolverSolutionCallback.__init__(self) self.__variables = variables self.__solution_count = 0 def on_solution_callback(self) -> None: self.__solution_count += 1 for v in self.__variables: print(f"{v}={self.value(v)}", end=" ") print() @property def solution_count(self) -> int: return self.__solution_count def main() -> None: """solve the CP+IS+FUN==TRUE cryptarithm.""" # Constraint programming engine model = cp_model.CpModel() base = 10 c = model.new_int_var(1, base - 1, "C") p = model.new_int_var(0, base - 1, "P") i = model.new_int_var(1, base - 1, "I") s = model.new_int_var(0, base - 1, "S") f = model.new_int_var(1, base - 1, "F") u = model.new_int_var(0, base - 1, "U") n = model.new_int_var(0, base - 1, "N") t = model.new_int_var(1, base - 1, "T") r = model.new_int_var(0, base - 1, "R") e = model.new_int_var(0, base - 1, "E") # We need to group variables in a list to use the constraint AllDifferent. letters = [c, p, i, s, f, u, n, t, r, e] # Verify that we have enough digits. assert base >= len(letters) # Define constraints. model.add_all_different(letters) # CP + IS + FUN = TRUE model.add( c * base + p + i * base + s + f * base * base + u * base + n == t * base * base * base + r * base * base + u * base + e ) # Creates a solver and solves the model. solver = cp_model.CpSolver() solution_printer = VarArraySolutionPrinter(letters) # Enumerate all solutions. solver.parameters.enumerate_all_solutions = True # Solve. status = solver.solve(model, solution_printer) # Statistics. print("\nStatistics") print(f" status : {solver.status_name(status)}") print(f" conflicts: {solver.num_conflicts}") print(f" branches : {solver.num_branches}") print(f" wall time: {solver.wall_time} s") print(f" sol found: {solution_printer.solution_count}") if __name__ == "__main__": main()
C++
// Cryptarithmetic puzzle // // First attempt to solve equation CP + IS + FUN = TRUE // where each letter represents a unique digit. // // This problem has 72 different solutions in base 10. #include <stdlib.h> #include <cstdint> #include "ortools/base/logging.h" #include "ortools/sat/cp_model.h" #include "ortools/sat/cp_model.pb.h" #include "ortools/sat/cp_model_solver.h" #include "ortools/sat/model.h" #include "ortools/sat/sat_parameters.pb.h" #include "ortools/util/sorted_interval_list.h" namespace operations_research { namespace sat { void CPIsFunSat() { // Instantiate the solver. CpModelBuilder cp_model; const int64_t kBase = 10; // Define decision variables. Domain digit(0, kBase - 1); Domain non_zero_digit(1, kBase - 1); IntVar c = cp_model.NewIntVar(non_zero_digit).WithName("C"); IntVar p = cp_model.NewIntVar(digit).WithName("P"); IntVar i = cp_model.NewIntVar(non_zero_digit).WithName("I"); IntVar s = cp_model.NewIntVar(digit).WithName("S"); IntVar f = cp_model.NewIntVar(non_zero_digit).WithName("F"); IntVar u = cp_model.NewIntVar(digit).WithName("U"); IntVar n = cp_model.NewIntVar(digit).WithName("N"); IntVar t = cp_model.NewIntVar(non_zero_digit).WithName("T"); IntVar r = cp_model.NewIntVar(digit).WithName("R"); IntVar e = cp_model.NewIntVar(digit).WithName("E"); // Define constraints. cp_model.AddAllDifferent({c, p, i, s, f, u, n, t, r, e}); // CP + IS + FUN = TRUE cp_model.AddEquality( c * kBase + p + i * kBase + s + f * kBase * kBase + u * kBase + n, kBase * kBase * kBase * t + kBase * kBase * r + kBase * u + e); Model model; int num_solutions = 0; model.Add(NewFeasibleSolutionObserver([&](const CpSolverResponse& response) { LOG(INFO) << "Solution " << num_solutions; LOG(INFO) << "C=" << SolutionIntegerValue(response, c) << " " << "P=" << SolutionIntegerValue(response, p) << " " << "I=" << SolutionIntegerValue(response, i) << " " << "S=" << SolutionIntegerValue(response, s) << " " << "F=" << SolutionIntegerValue(response, f) << " " << "U=" << SolutionIntegerValue(response, u) << " " << "N=" << SolutionIntegerValue(response, n) << " " << "T=" << SolutionIntegerValue(response, t) << " " << "R=" << SolutionIntegerValue(response, r) << " " << "E=" << SolutionIntegerValue(response, e); num_solutions++; })); // Tell the solver to enumerate all solutions. SatParameters parameters; parameters.set_enumerate_all_solutions(true); model.Add(NewSatParameters(parameters)); const CpSolverResponse response = SolveCpModel(cp_model.Build(), &model); LOG(INFO) << "Number of solutions found: " << num_solutions; // Statistics. LOG(INFO) << "Statistics"; LOG(INFO) << CpSolverResponseStats(response); } } // namespace sat } // namespace operations_research int main(int argc, char** argv) { operations_research::sat::CPIsFunSat(); return EXIT_SUCCESS; }
Java
package com.google.ortools.sat.samples; import com.google.ortools.Loader; import com.google.ortools.sat.CpModel; import com.google.ortools.sat.CpSolver; import com.google.ortools.sat.CpSolverSolutionCallback; import com.google.ortools.sat.IntVar; import com.google.ortools.sat.LinearExpr; /** Cryptarithmetic puzzle. */ public final class CpIsFunSat { static class VarArraySolutionPrinter extends CpSolverSolutionCallback { public VarArraySolutionPrinter(IntVar[] variables) { variableArray = variables; } @Override public void onSolutionCallback() { for (IntVar v : variableArray) { System.out.printf(" %s = %d", v.getName(), value(v)); } System.out.println(); solutionCount++; } public int getSolutionCount() { return solutionCount; } private int solutionCount; private final IntVar[] variableArray; } public static void main(String[] args) throws Exception { Loader.loadNativeLibraries(); // Create the model. CpModel model = new CpModel(); int base = 10; IntVar c = model.newIntVar(1, base - 1, "C"); IntVar p = model.newIntVar(0, base - 1, "P"); IntVar i = model.newIntVar(1, base - 1, "I"); IntVar s = model.newIntVar(0, base - 1, "S"); IntVar f = model.newIntVar(1, base - 1, "F"); IntVar u = model.newIntVar(0, base - 1, "U"); IntVar n = model.newIntVar(0, base - 1, "N"); IntVar t = model.newIntVar(1, base - 1, "T"); IntVar r = model.newIntVar(0, base - 1, "R"); IntVar e = model.newIntVar(0, base - 1, "E"); // We need to group variables in a list to use the constraint AllDifferent. IntVar[] letters = new IntVar[] {c, p, i, s, f, u, n, t, r, e}; // Define constraints. model.addAllDifferent(letters); // CP + IS + FUN = TRUE model.addEquality(LinearExpr.weightedSum(new IntVar[] {c, p, i, s, f, u, n, t, r, u, e}, new long[] {base, 1, base, 1, base * base, base, 1, -base * base * base, -base * base, -base, -1}), 0); // Create a solver and solve the model. CpSolver solver = new CpSolver(); VarArraySolutionPrinter cb = new VarArraySolutionPrinter(letters); // Tell the solver to enumerate all solutions. solver.getParameters().setEnumerateAllSolutions(true); // And solve. solver.solve(model, cb); // Statistics. System.out.println("Statistics"); System.out.println(" - conflicts : " + solver.numConflicts()); System.out.println(" - branches : " + solver.numBranches()); System.out.println(" - wall time : " + solver.wallTime() + " s"); System.out.println(" - solutions : " + cb.getSolutionCount()); } private CpIsFunSat() {} }
C#
// Cryptarithmetic puzzle // // First attempt to solve equation CP + IS + FUN = TRUE // where each letter represents a unique digit. // // This problem has 72 different solutions in base 10. using System; using Google.OrTools.Sat; public class CpIsFunSat { public class VarArraySolutionPrinter : CpSolverSolutionCallback { public VarArraySolutionPrinter(IntVar[] variables) { variables_ = variables; } public override void OnSolutionCallback() { { foreach (IntVar v in variables_) { Console.Write(String.Format(" {0}={1}", v.ToString(), Value(v))); } Console.WriteLine(); solution_count_++; } } public int SolutionCount() { return solution_count_; } private int solution_count_; private IntVar[] variables_; } // Solve the CP+IS+FUN==TRUE cryptarithm. static void Main() { // Constraint programming engine CpModel model = new CpModel(); int kBase = 10; IntVar c = model.NewIntVar(1, kBase - 1, "C"); IntVar p = model.NewIntVar(0, kBase - 1, "P"); IntVar i = model.NewIntVar(1, kBase - 1, "I"); IntVar s = model.NewIntVar(0, kBase - 1, "S"); IntVar f = model.NewIntVar(1, kBase - 1, "F"); IntVar u = model.NewIntVar(0, kBase - 1, "U"); IntVar n = model.NewIntVar(0, kBase - 1, "N"); IntVar t = model.NewIntVar(1, kBase - 1, "T"); IntVar r = model.NewIntVar(0, kBase - 1, "R"); IntVar e = model.NewIntVar(0, kBase - 1, "E"); // We need to group variables in a list to use the constraint AllDifferent. IntVar[] letters = new IntVar[] { c, p, i, s, f, u, n, t, r, e }; // Define constraints. model.AddAllDifferent(letters); // CP + IS + FUN = TRUE model.Add(c * kBase + p + i * kBase + s + f * kBase * kBase + u * kBase + n == t * kBase * kBase * kBase + r * kBase * kBase + u * kBase + e); // Creates a solver and solves the model. CpSolver solver = new CpSolver(); VarArraySolutionPrinter cb = new VarArraySolutionPrinter(letters); // Search for all solutions. solver.StringParameters = "enumerate_all_solutions:true"; // And solve. solver.Solve(model, cb); Console.WriteLine("Statistics"); Console.WriteLine($" conflicts : {solver.NumConflicts()}"); Console.WriteLine($" branches : {solver.NumBranches()}"); Console.WriteLine($" wall time : {solver.WallTime()} s"); Console.WriteLine($" number of solutions found: {cb.SolutionCount()}"); } }
Soluzione CP originale
In questo caso tratteremo la base come variabile, in modo da poter risolvere l'equazione per basi più elevate. (Non possono esistere soluzioni di base inferiori per CP + IS + FUN = TRUE
poiché le dieci lettere devono essere tutte diverse.)
Importa le librerie
Il seguente codice importa la libreria richiesta.
Python
from ortools.constraint_solver import pywrapcp
C++
#include <cstdint> #include <vector> #include "absl/flags/flag.h" #include "absl/log/flags.h" #include "ortools/base/init_google.h" #include "ortools/base/logging.h" #include "ortools/constraint_solver/constraint_solver.h"
Java
C#
using System; using Google.OrTools.ConstraintSolver;
Creazione del risolutore
Il primo passaggio consiste nel creare Solver
.
Python
solver = pywrapcp.Solver("CP is fun!")
C++
Solver solver("CP is fun!");
Java
Solver solver = new Solver("CP is fun!");
C#
Solver solver = new Solver("CP is fun!");
Definizione delle variabili
Il primo passaggio consiste nel creare un IntVar
per ogni lettera. Distinguiamo tra
le lettere che possono potenzialmente essere pari a zero e quelle che non possono esserlo (C
, I
, F
e T
).
Successivamente, creiamo un array contenente un nuovo IntVar
per ogni lettera. Questo è necessario solo
perché quando definiamo i nostri vincoli, useremo
AllDifferent
, quindi abbiamo bisogno di un array per il quale ogni elemento deve differire.
Infine, verifichiamo che la nostra base sia grande almeno quanto il numero di lettere; in caso contrario, non c'è soluzione.
Python
base = 10 # Decision variables. digits = list(range(0, base)) digits_without_zero = list(range(1, base)) c = solver.IntVar(digits_without_zero, "C") p = solver.IntVar(digits, "P") i = solver.IntVar(digits_without_zero, "I") s = solver.IntVar(digits, "S") f = solver.IntVar(digits_without_zero, "F") u = solver.IntVar(digits, "U") n = solver.IntVar(digits, "N") t = solver.IntVar(digits_without_zero, "T") r = solver.IntVar(digits, "R") e = solver.IntVar(digits, "E") # We need to group variables in a list to use the constraint AllDifferent. letters = [c, p, i, s, f, u, n, t, r, e] # Verify that we have enough digits. assert base >= len(letters)
C++
const int64_t kBase = 10; // Define decision variables. IntVar* const c = solver.MakeIntVar(1, kBase - 1, "C"); IntVar* const p = solver.MakeIntVar(0, kBase - 1, "P"); IntVar* const i = solver.MakeIntVar(1, kBase - 1, "I"); IntVar* const s = solver.MakeIntVar(0, kBase - 1, "S"); IntVar* const f = solver.MakeIntVar(1, kBase - 1, "F"); IntVar* const u = solver.MakeIntVar(0, kBase - 1, "U"); IntVar* const n = solver.MakeIntVar(0, kBase - 1, "N"); IntVar* const t = solver.MakeIntVar(1, kBase - 1, "T"); IntVar* const r = solver.MakeIntVar(0, kBase - 1, "R"); IntVar* const e = solver.MakeIntVar(0, kBase - 1, "E"); // We need to group variables in a vector to be able to use // the global constraint AllDifferent std::vector<IntVar*> letters{c, p, i, s, f, u, n, t, r, e}; // Check if we have enough digits CHECK_GE(kBase, letters.size());
Java
final int base = 10; // Decision variables. final IntVar c = solver.makeIntVar(1, base - 1, "C"); final IntVar p = solver.makeIntVar(0, base - 1, "P"); final IntVar i = solver.makeIntVar(1, base - 1, "I"); final IntVar s = solver.makeIntVar(0, base - 1, "S"); final IntVar f = solver.makeIntVar(1, base - 1, "F"); final IntVar u = solver.makeIntVar(0, base - 1, "U"); final IntVar n = solver.makeIntVar(0, base - 1, "N"); final IntVar t = solver.makeIntVar(1, base - 1, "T"); final IntVar r = solver.makeIntVar(0, base - 1, "R"); final IntVar e = solver.makeIntVar(0, base - 1, "E"); // Group variables in a vector so that we can use AllDifferent. final IntVar[] letters = new IntVar[] {c, p, i, s, f, u, n, t, r, e}; // Verify that we have enough digits. if (base < letters.length) { throw new Exception("base < letters.Length"); }
C#
const int kBase = 10; // Decision variables. IntVar c = solver.MakeIntVar(1, kBase - 1, "C"); IntVar p = solver.MakeIntVar(0, kBase - 1, "P"); IntVar i = solver.MakeIntVar(1, kBase - 1, "I"); IntVar s = solver.MakeIntVar(0, kBase - 1, "S"); IntVar f = solver.MakeIntVar(1, kBase - 1, "F"); IntVar u = solver.MakeIntVar(0, kBase - 1, "U"); IntVar n = solver.MakeIntVar(0, kBase - 1, "N"); IntVar t = solver.MakeIntVar(1, kBase - 1, "T"); IntVar r = solver.MakeIntVar(0, kBase - 1, "R"); IntVar e = solver.MakeIntVar(0, kBase - 1, "E"); // Group variables in a vector so that we can use AllDifferent. IntVar[] letters = new IntVar[] { c, p, i, s, f, u, n, t, r, e }; // Verify that we have enough digits. if (kBase < letters.Length) { throw new Exception("kBase < letters.Length"); }
Definizione dei vincoli
Ora che abbiamo definito le variabili, il passaggio successivo è definire i vincoli.
Innanzitutto, aggiungiamo il vincolo AllDifferent
, forzando ogni lettera ad avere una cifra diversa.
Quindi, aggiungiamo il vincolo CP + IS + FUN = TRUE
. I programmi di esempio lo fanno
in modi diversi.
Python
solver.Add(solver.AllDifferent(letters)) # CP + IS + FUN = TRUE solver.Add( p + s + n + base * (c + i + u) + base * base * f == e + base * u + base * base * r + base * base * base * t )
C++
// Define constraints. solver.AddConstraint(solver.MakeAllDifferent(letters)); // CP + IS + FUN = TRUE IntVar* const term1 = MakeBaseLine2(&solver, c, p, kBase); IntVar* const term2 = MakeBaseLine2(&solver, i, s, kBase); IntVar* const term3 = MakeBaseLine3(&solver, f, u, n, kBase); IntVar* const sum_terms = solver.MakeSum(solver.MakeSum(term1, term2), term3)->Var(); IntVar* const sum = MakeBaseLine4(&solver, t, r, u, e, kBase); solver.AddConstraint(solver.MakeEquality(sum_terms, sum));
Java
solver.addConstraint(solver.makeAllDifferent(letters)); // CP + IS + FUN = TRUE final IntVar sum1 = solver .makeSum(new IntVar[] {p, s, n, solver.makeProd(solver.makeSum(new IntVar[] {c, i, u}).var(), base).var(), solver.makeProd(f, base * base).var()}) .var(); final IntVar sum2 = solver .makeSum(new IntVar[] {e, solver.makeProd(u, base).var(), solver.makeProd(r, base * base).var(), solver.makeProd(t, base * base * base).var()}) .var(); solver.addConstraint(solver.makeEquality(sum1, sum2));
C#
solver.Add(letters.AllDifferent()); // CP + IS + FUN = TRUE solver.Add(p + s + n + kBase * (c + i + u) + kBase * kBase * f == e + kBase * u + kBase * kBase * r + kBase * kBase * kBase * t);
Richiamo del risolutore
Ora che abbiamo le nostre variabili e i nostri vincoli, possiamo risolvere il problema.
Di seguito è mostrato il codice della stampante della soluzione, che mostra ogni soluzione man mano che il risolutore la trova.
Poiché esistono più soluzioni al nostro problema, eseguiamo l'iterazione
delle soluzioni con un loop while solver.NextSolution()
. Se stessimo solo cercando
di trovare un'unica soluzione, useremmo questo idioma:\
if (solver.NextSolution()) { // Print solution. } else { // Print that no solution could be found. }
Python
solution_count = 0 db = solver.Phase(letters, solver.INT_VAR_DEFAULT, solver.INT_VALUE_DEFAULT) solver.NewSearch(db) while solver.NextSolution(): print(letters) # Is CP + IS + FUN = TRUE? assert ( base * c.Value() + p.Value() + base * i.Value() + s.Value() + base * base * f.Value() + base * u.Value() + n.Value() == base * base * base * t.Value() + base * base * r.Value() + base * u.Value() + e.Value() ) solution_count += 1 solver.EndSearch() print(f"Number of solutions found: {solution_count}")
C++
int num_solutions = 0; // Create decision builder to search for solutions. DecisionBuilder* const db = solver.MakePhase( letters, Solver::CHOOSE_FIRST_UNBOUND, Solver::ASSIGN_MIN_VALUE); solver.NewSearch(db); while (solver.NextSolution()) { LOG(INFO) << "C=" << c->Value() << " " << "P=" << p->Value() << " " << "I=" << i->Value() << " " << "S=" << s->Value() << " " << "F=" << f->Value() << " " << "U=" << u->Value() << " " << "N=" << n->Value() << " " << "T=" << t->Value() << " " << "R=" << r->Value() << " " << "E=" << e->Value(); // Is CP + IS + FUN = TRUE? CHECK_EQ(p->Value() + s->Value() + n->Value() + kBase * (c->Value() + i->Value() + u->Value()) + kBase * kBase * f->Value(), e->Value() + kBase * u->Value() + kBase * kBase * r->Value() + kBase * kBase * kBase * t->Value()); num_solutions++; } solver.EndSearch(); LOG(INFO) << "Number of solutions found: " << num_solutions;
Java
int countSolution = 0; // Create the decision builder to search for solutions. final DecisionBuilder db = solver.makePhase(letters, Solver.CHOOSE_FIRST_UNBOUND, Solver.ASSIGN_MIN_VALUE); solver.newSearch(db); while (solver.nextSolution()) { System.out.println("C=" + c.value() + " P=" + p.value()); System.out.println(" I=" + i.value() + " S=" + s.value()); System.out.println(" F=" + f.value() + " U=" + u.value()); System.out.println(" N=" + n.value() + " T=" + t.value()); System.out.println(" R=" + r.value() + " E=" + e.value()); // Is CP + IS + FUN = TRUE? if (p.value() + s.value() + n.value() + base * (c.value() + i.value() + u.value()) + base * base * f.value() != e.value() + base * u.value() + base * base * r.value() + base * base * base * t.value()) { throw new Exception("CP + IS + FUN != TRUE"); } countSolution++; } solver.endSearch(); System.out.println("Number of solutions found: " + countSolution);
C#
int SolutionCount = 0; // Create the decision builder to search for solutions. DecisionBuilder db = solver.MakePhase(letters, Solver.CHOOSE_FIRST_UNBOUND, Solver.ASSIGN_MIN_VALUE); solver.NewSearch(db); while (solver.NextSolution()) { Console.Write("C=" + c.Value() + " P=" + p.Value()); Console.Write(" I=" + i.Value() + " S=" + s.Value()); Console.Write(" F=" + f.Value() + " U=" + u.Value()); Console.Write(" N=" + n.Value() + " T=" + t.Value()); Console.Write(" R=" + r.Value() + " E=" + e.Value()); Console.WriteLine(); // Is CP + IS + FUN = TRUE? if (p.Value() + s.Value() + n.Value() + kBase * (c.Value() + i.Value() + u.Value()) + kBase * kBase * f.Value() != e.Value() + kBase * u.Value() + kBase * kBase * r.Value() + kBase * kBase * kBase * t.Value()) { throw new Exception("CP + IS + FUN != TRUE"); } SolutionCount++; } solver.EndSearch(); Console.WriteLine($"Number of solutions found: {SolutionCount}");
Completa i programmi
Ecco i programmi completi.
Python
"""Cryptarithmetic puzzle. First attempt to solve equation CP + IS + FUN = TRUE where each letter represents a unique digit. This problem has 72 different solutions in base 10. """ from ortools.constraint_solver import pywrapcp def main(): # Constraint programming engine solver = pywrapcp.Solver("CP is fun!") base = 10 # Decision variables. digits = list(range(0, base)) digits_without_zero = list(range(1, base)) c = solver.IntVar(digits_without_zero, "C") p = solver.IntVar(digits, "P") i = solver.IntVar(digits_without_zero, "I") s = solver.IntVar(digits, "S") f = solver.IntVar(digits_without_zero, "F") u = solver.IntVar(digits, "U") n = solver.IntVar(digits, "N") t = solver.IntVar(digits_without_zero, "T") r = solver.IntVar(digits, "R") e = solver.IntVar(digits, "E") # We need to group variables in a list to use the constraint AllDifferent. letters = [c, p, i, s, f, u, n, t, r, e] # Verify that we have enough digits. assert base >= len(letters) # Define constraints. solver.Add(solver.AllDifferent(letters)) # CP + IS + FUN = TRUE solver.Add( p + s + n + base * (c + i + u) + base * base * f == e + base * u + base * base * r + base * base * base * t ) solution_count = 0 db = solver.Phase(letters, solver.INT_VAR_DEFAULT, solver.INT_VALUE_DEFAULT) solver.NewSearch(db) while solver.NextSolution(): print(letters) # Is CP + IS + FUN = TRUE? assert ( base * c.Value() + p.Value() + base * i.Value() + s.Value() + base * base * f.Value() + base * u.Value() + n.Value() == base * base * base * t.Value() + base * base * r.Value() + base * u.Value() + e.Value() ) solution_count += 1 solver.EndSearch() print(f"Number of solutions found: {solution_count}") if __name__ == "__main__": main()
C++
// Cryptarithmetic puzzle // // First attempt to solve equation CP + IS + FUN = TRUE // where each letter represents a unique digit. // // This problem has 72 different solutions in base 10. #include <cstdint> #include <vector> #include "absl/flags/flag.h" #include "absl/log/flags.h" #include "ortools/base/init_google.h" #include "ortools/base/logging.h" #include "ortools/constraint_solver/constraint_solver.h" namespace operations_research { // Helper functions. IntVar* MakeBaseLine2(Solver* s, IntVar* const v1, IntVar* const v2, const int64_t base) { return s->MakeSum(s->MakeProd(v1, base), v2)->Var(); } IntVar* MakeBaseLine3(Solver* s, IntVar* const v1, IntVar* const v2, IntVar* const v3, const int64_t base) { std::vector<IntVar*> tmp_vars; std::vector<int64_t> coefficients; tmp_vars.push_back(v1); coefficients.push_back(base * base); tmp_vars.push_back(v2); coefficients.push_back(base); tmp_vars.push_back(v3); coefficients.push_back(1); return s->MakeScalProd(tmp_vars, coefficients)->Var(); } IntVar* MakeBaseLine4(Solver* s, IntVar* const v1, IntVar* const v2, IntVar* const v3, IntVar* const v4, const int64_t base) { std::vector<IntVar*> tmp_vars; std::vector<int64_t> coefficients; tmp_vars.push_back(v1); coefficients.push_back(base * base * base); tmp_vars.push_back(v2); coefficients.push_back(base * base); tmp_vars.push_back(v3); coefficients.push_back(base); tmp_vars.push_back(v4); coefficients.push_back(1); return s->MakeScalProd(tmp_vars, coefficients)->Var(); } void CPIsFunCp() { // Instantiate the solver. Solver solver("CP is fun!"); const int64_t kBase = 10; // Define decision variables. IntVar* const c = solver.MakeIntVar(1, kBase - 1, "C"); IntVar* const p = solver.MakeIntVar(0, kBase - 1, "P"); IntVar* const i = solver.MakeIntVar(1, kBase - 1, "I"); IntVar* const s = solver.MakeIntVar(0, kBase - 1, "S"); IntVar* const f = solver.MakeIntVar(1, kBase - 1, "F"); IntVar* const u = solver.MakeIntVar(0, kBase - 1, "U"); IntVar* const n = solver.MakeIntVar(0, kBase - 1, "N"); IntVar* const t = solver.MakeIntVar(1, kBase - 1, "T"); IntVar* const r = solver.MakeIntVar(0, kBase - 1, "R"); IntVar* const e = solver.MakeIntVar(0, kBase - 1, "E"); // We need to group variables in a vector to be able to use // the global constraint AllDifferent std::vector<IntVar*> letters{c, p, i, s, f, u, n, t, r, e}; // Check if we have enough digits CHECK_GE(kBase, letters.size()); // Define constraints. solver.AddConstraint(solver.MakeAllDifferent(letters)); // CP + IS + FUN = TRUE IntVar* const term1 = MakeBaseLine2(&solver, c, p, kBase); IntVar* const term2 = MakeBaseLine2(&solver, i, s, kBase); IntVar* const term3 = MakeBaseLine3(&solver, f, u, n, kBase); IntVar* const sum_terms = solver.MakeSum(solver.MakeSum(term1, term2), term3)->Var(); IntVar* const sum = MakeBaseLine4(&solver, t, r, u, e, kBase); solver.AddConstraint(solver.MakeEquality(sum_terms, sum)); int num_solutions = 0; // Create decision builder to search for solutions. DecisionBuilder* const db = solver.MakePhase( letters, Solver::CHOOSE_FIRST_UNBOUND, Solver::ASSIGN_MIN_VALUE); solver.NewSearch(db); while (solver.NextSolution()) { LOG(INFO) << "C=" << c->Value() << " " << "P=" << p->Value() << " " << "I=" << i->Value() << " " << "S=" << s->Value() << " " << "F=" << f->Value() << " " << "U=" << u->Value() << " " << "N=" << n->Value() << " " << "T=" << t->Value() << " " << "R=" << r->Value() << " " << "E=" << e->Value(); // Is CP + IS + FUN = TRUE? CHECK_EQ(p->Value() + s->Value() + n->Value() + kBase * (c->Value() + i->Value() + u->Value()) + kBase * kBase * f->Value(), e->Value() + kBase * u->Value() + kBase * kBase * r->Value() + kBase * kBase * kBase * t->Value()); num_solutions++; } solver.EndSearch(); LOG(INFO) << "Number of solutions found: " << num_solutions; } } // namespace operations_research int main(int argc, char** argv) { InitGoogle(argv[0], &argc, &argv, true); absl::SetFlag(&FLAGS_stderrthreshold, 0); operations_research::CPIsFunCp(); return EXIT_SUCCESS; }
Java
// Cryptarithmetic puzzle // // First attempt to solve equation CP + IS + FUN = TRUE // where each letter represents a unique digit. // // This problem has 72 different solutions in base 10. package com.google.ortools.constraintsolver.samples; import com.google.ortools.Loader; import com.google.ortools.constraintsolver.DecisionBuilder; import com.google.ortools.constraintsolver.IntVar; import com.google.ortools.constraintsolver.Solver; /** Cryptarithmetic puzzle. */ public final class CpIsFunCp { public static void main(String[] args) throws Exception { Loader.loadNativeLibraries(); // Instantiate the solver. Solver solver = new Solver("CP is fun!"); final int base = 10; // Decision variables. final IntVar c = solver.makeIntVar(1, base - 1, "C"); final IntVar p = solver.makeIntVar(0, base - 1, "P"); final IntVar i = solver.makeIntVar(1, base - 1, "I"); final IntVar s = solver.makeIntVar(0, base - 1, "S"); final IntVar f = solver.makeIntVar(1, base - 1, "F"); final IntVar u = solver.makeIntVar(0, base - 1, "U"); final IntVar n = solver.makeIntVar(0, base - 1, "N"); final IntVar t = solver.makeIntVar(1, base - 1, "T"); final IntVar r = solver.makeIntVar(0, base - 1, "R"); final IntVar e = solver.makeIntVar(0, base - 1, "E"); // Group variables in a vector so that we can use AllDifferent. final IntVar[] letters = new IntVar[] {c, p, i, s, f, u, n, t, r, e}; // Verify that we have enough digits. if (base < letters.length) { throw new Exception("base < letters.Length"); } // Define constraints. solver.addConstraint(solver.makeAllDifferent(letters)); // CP + IS + FUN = TRUE final IntVar sum1 = solver .makeSum(new IntVar[] {p, s, n, solver.makeProd(solver.makeSum(new IntVar[] {c, i, u}).var(), base).var(), solver.makeProd(f, base * base).var()}) .var(); final IntVar sum2 = solver .makeSum(new IntVar[] {e, solver.makeProd(u, base).var(), solver.makeProd(r, base * base).var(), solver.makeProd(t, base * base * base).var()}) .var(); solver.addConstraint(solver.makeEquality(sum1, sum2)); int countSolution = 0; // Create the decision builder to search for solutions. final DecisionBuilder db = solver.makePhase(letters, Solver.CHOOSE_FIRST_UNBOUND, Solver.ASSIGN_MIN_VALUE); solver.newSearch(db); while (solver.nextSolution()) { System.out.println("C=" + c.value() + " P=" + p.value()); System.out.println(" I=" + i.value() + " S=" + s.value()); System.out.println(" F=" + f.value() + " U=" + u.value()); System.out.println(" N=" + n.value() + " T=" + t.value()); System.out.println(" R=" + r.value() + " E=" + e.value()); // Is CP + IS + FUN = TRUE? if (p.value() + s.value() + n.value() + base * (c.value() + i.value() + u.value()) + base * base * f.value() != e.value() + base * u.value() + base * base * r.value() + base * base * base * t.value()) { throw new Exception("CP + IS + FUN != TRUE"); } countSolution++; } solver.endSearch(); System.out.println("Number of solutions found: " + countSolution); } private CpIsFunCp() {} }
C#
// Cryptarithmetic puzzle // // First attempt to solve equation CP + IS + FUN = TRUE // where each letter represents a unique digit. // // This problem has 72 different solutions in base 10. using System; using Google.OrTools.ConstraintSolver; public class CpIsFunCp { public static void Main(String[] args) { // Instantiate the solver. Solver solver = new Solver("CP is fun!"); const int kBase = 10; // Decision variables. IntVar c = solver.MakeIntVar(1, kBase - 1, "C"); IntVar p = solver.MakeIntVar(0, kBase - 1, "P"); IntVar i = solver.MakeIntVar(1, kBase - 1, "I"); IntVar s = solver.MakeIntVar(0, kBase - 1, "S"); IntVar f = solver.MakeIntVar(1, kBase - 1, "F"); IntVar u = solver.MakeIntVar(0, kBase - 1, "U"); IntVar n = solver.MakeIntVar(0, kBase - 1, "N"); IntVar t = solver.MakeIntVar(1, kBase - 1, "T"); IntVar r = solver.MakeIntVar(0, kBase - 1, "R"); IntVar e = solver.MakeIntVar(0, kBase - 1, "E"); // Group variables in a vector so that we can use AllDifferent. IntVar[] letters = new IntVar[] { c, p, i, s, f, u, n, t, r, e }; // Verify that we have enough digits. if (kBase < letters.Length) { throw new Exception("kBase < letters.Length"); } // Define constraints. solver.Add(letters.AllDifferent()); // CP + IS + FUN = TRUE solver.Add(p + s + n + kBase * (c + i + u) + kBase * kBase * f == e + kBase * u + kBase * kBase * r + kBase * kBase * kBase * t); int SolutionCount = 0; // Create the decision builder to search for solutions. DecisionBuilder db = solver.MakePhase(letters, Solver.CHOOSE_FIRST_UNBOUND, Solver.ASSIGN_MIN_VALUE); solver.NewSearch(db); while (solver.NextSolution()) { Console.Write("C=" + c.Value() + " P=" + p.Value()); Console.Write(" I=" + i.Value() + " S=" + s.Value()); Console.Write(" F=" + f.Value() + " U=" + u.Value()); Console.Write(" N=" + n.Value() + " T=" + t.Value()); Console.Write(" R=" + r.Value() + " E=" + e.Value()); Console.WriteLine(); // Is CP + IS + FUN = TRUE? if (p.Value() + s.Value() + n.Value() + kBase * (c.Value() + i.Value() + u.Value()) + kBase * kBase * f.Value() != e.Value() + kBase * u.Value() + kBase * kBase * r.Value() + kBase * kBase * kBase * t.Value()) { throw new Exception("CP + IS + FUN != TRUE"); } SolutionCount++; } solver.EndSearch(); Console.WriteLine($"Number of solutions found: {SolutionCount}"); } }