DFS-Sudoku（poj2676）

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;
int map[10][10], hang[10][10], lie[10][10], kuai[10][10], cnt;
int cal(int i, int j)//输入行列号，判断他在哪一块里
{
	return ((i-1)/3)+(((j-1)/3)*3+1);
}
struct point
{
	int x;
	int y;
}p[100];
int dfs(int n)
{
	if(n > cnt) return 1;
	int xx = p[n].x, yy = p[n].y;
	for(int i = 1; i <= 9; i++)
	{
		if(!hang[xx][i] && !lie[yy][i] && !kuai[cal(xx, yy)][i])
		{
			hang[xx][i] = 1;
			lie[yy][i] = 1;
			kuai[cal(xx, yy)][i] = 1;
			map[xx][yy] = i;
			if(dfs(n+1)) return 1;
			hang[xx][i] = 0;
			lie[yy][i] = 0;
			kuai[cal(xx, yy)][i] = 0;
		}
	}
	return 0;
}
int main()
{
	int t;
	cin>>t;
	while(t--)
	{
		memset(map, 0, sizeof(map));
		memset(hang, 0, sizeof(hang));
		memset(lie,0 ,sizeof(lie));
		memset(kuai, 0, sizeof(kuai));
		cnt = 0;
		char str[10];
		for(int i = 1; i <= 9; i++)
		{
			scanf("%s", str);
			for(int j = 1; j <= 9; j++)
			{
				int x = str[j-1]-48;
				if(x)
				{
					map[i][j] = x;
					hang[i][x] = 1;
					lie[j][x] = 1;
					kuai[cal(i, j)][x] = 1;
				}
				else
				{
					p[++cnt].x = i;
					p[cnt].y = j;
				}
			}
		}
		dfs(1);
		for(int i = 1; i <= 9; i++)
		{
			for(int j = 1; j <= 9; j++)
			{
				cout<<map[i][j];
			}
			cout<<endl;
		}
	}
	return 0;
}