解数独算法－－C++代码实现
今天公司比较闲，又碰巧对数独感兴趣，就写了个解数独的代码，方法比较笨，用的回溯法。也有一些需要优化的地方，要下班了，就匆匆发出来了，欢迎大伙拍砖，12年毕业的小白，大伙手下留情。
改天有时间再用MFC写个界面。好了，废话不说，代码奉上。
#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( set_colm == 0)
{
line--;
set_colm = 8;
}
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}
};
//test
/*
int a[9][9] = {
{8,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,6,8},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0}
};
*/
TotalNumbers( a, 9, 9 );
success( a, 0, 0 );
print(a);
}
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
你的代码解不了上面的
