解数独算法－－C++实现

时间比较仓促，未优化。大牛看客，勿笑话。当然有好的建议，我洗耳恭听。若有时间再用MFC写一个界面。

好了，废话不多说，代码如下：

#include <iostream>using namespace std;//可选数字int candidate[] = {1,2,3,4,5,6,7,8,9};//标记这个空格是否为原始数据int g_a[9][9] = {0};//打印函数void print( int (*a)[9] ){for( int i = 0; i < 9; i++ ){for( int j = 0; j < 9; j++ ){cout << a[i][j] << " ";}cout << endl;}cout << endl;}//判断可以放哪些数字void ConfirmCandidate( int (*a)[9], int i, int j ){for( int i_candidate = 0; i_candidate < 9; i_candidate++ )candidate[i_candidate] = i_candidate+1;for( int colm = 0; colm < 9; colm++ ){if( a[i][colm] != 0 )candidate[a[i][colm]-1] = 0;}for( int line = 0; line < 9; line++ ){if( a[line][j] != 0 )candidate[a[line][j]-1] = 0;}for( int line = i/3*3; line < i/3*3+3; line++ ){for( int colm = j/3*3; colm < j/3*3+3; colm++ )if( a[line][colm] != 0 )candidate[a[line][colm]-1] = 0;}}//标记每个空格位置void TotalNumbers( int (*a)[9], int i, int j ){for( int line = 0; line < i; line++ ){for( int colm = 0; colm < j; colm++ )if( a[line][colm] == 0 ){g_a[line][colm] = 1;}}}//判断所填数字是否正确bool JudgeValue( int (*a)[9],int i, int j ){//同一行有无重复数字for( int colm = 0; colm < 9; colm++ ){if( a[i][colm] == a[i][j] && j != colm )return false;}//同一列有无重复数字for( int line = 0; line < 9; line++ ){if( a[line][j] == a[i][j] && i != line )return false;}//一个3*3的方格内有无重复数字for( int line = i/3*3; line < i/3*3+3; line++ ){for( int colm = j/3*3; colm < j/3*3+3; colm++ )if( a[line][colm] == a[i][j] && i != line && j != colm )return false;}return true;}//判断是否成功bool success( int(*a)[9], int i, int j ){if( i < 0 || j < 0 ) return false;int line = i;int colm = j;for( ; line < 9; line++, colm = 0 ){for( ; colm < 9; colm++ ){//cout << "line = " << line <<"  colm = " << colm << endl;//if( colm == 8 && line == 8 ) return true;if( a[line][colm] != 0 && g_a[line][colm] == 0 ) continue;ConfirmCandidate(a, line, colm);for(int c = 0; c < 9; c++ ){if( candidate[c] > a[line][colm] ){a[line][colm] = candidate[c];/**TEST*测试可选数字*//*for(int i = 0; i < 9; i++ )cout << candidate[i] << " ";cout << endl << endl;*///print(a);//判断放入的值是否正确bool bRet = JudgeValue( a, line, colm );if(!bRet) {//cout << "bRet  is  false" << endl;}else{//cout << "bRet  is  true" << endl;break;}}else if( c == 8 && candidate[c] <= a[line][colm] ){//cout << "line = " << line <<"  colm = " << colm << endl;int set_colm = 8;a[line][colm] = 0;if( colm == 0 ){while( g_a[line-1][set_colm] == 0){if( set_colm == 0) {line--;set_colm = 8;}else set_colm--;}return success( a, line - 1, set_colm);}else{while( g_a[line][colm-1] == 0){if( colm-1 == 0) {line--;colm = 9;}else colm--;}return success( a ,line, colm-1 );}}}}}return true;}int main(){//initialization/*int a[9][9] = {{8,0,0,0,0,0,0,0,0},{0,0,3,6,0,0,0,0,0},{0,7,0,0,9,0,2,0,0},{0,5,0,0,0,7,0,0,0},{0,0,0,0,4,5,7,0,0},{0,0,7,1,0,0,0,3,0},{0,0,1,0,0,0,0,6,8},{0,0,8,5,0,0,0,1,0},{0,9,0,0,0,0,4,0,0}};*///testint a[9][9] = {{0,5,0,0,0,0,0,0,0},{0,7,3,1,0,0,2,5,0},{1,0,2,5,0,0,7,6,0},{0,0,0,0,0,8,0,2,0},{0,8,0,0,2,1,0,0,0},{0,3,4,7,6,0,8,0,0},{0,0,0,6,8,0,0,4,1},{0,0,0,0,0,7,0,0,0},{0,0,0,0,1,4,0,0,0}};TotalNumbers( a, 9, 9 );success( a, 0, 0 );print(a);}