POJ 2676

题目链接 ：http://poj.org/problem?id=2676

 

Source Code 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int num[10][10] ,col[10][10] ,row[10][10] ,g[10][10] ,flag;
void dfs (int count) {
     if (count == 81) {
          flag = 1;
          for (int i = 0 ;i < 9 ;i++) {
               for (int j = 0 ;j < 9 ;j++)
               printf("%d",num[i][j]);
               printf("\n");
          }
          return ;
     }
     int x = count / 9 ,y = count % 9;
     if (num[x][y] != 0) {
          dfs(count + 1);
          return ;
     }
     else {
          int k = (x / 3) * 3 + y / 3;
          for (int j = 1 ;j <= 9 ;j++) {
                if (!row[x][j] && !col[y][j] && !g[k][j]) {
                     row[x][j] = 1;
                     col[y][j] = 1;
                     g[k][j] = 1;
                     num[x][y] = j;
                     dfs(count + 1);
                     if (flag) return ;
                     row[x][j] = 0;
                     col[y][j] = 0;
                     g[k][j] = 0;
                     num[x][y] = 0;
                }
          }
     }
}
int main () {
     int n;
     char arr[10];
     scanf ("%d",&n);
     while (n--) {
           flag = 0;
           memset (col ,0 ,sizeof(col));
           memset (row ,0 ,sizeof(row));
           memset (g ,0 ,sizeof(g));
           for (int i = 0 ;i < 9 ;i++) {
                scanf ("%s",arr);
                for (int j = 0 ;j < 9 ;j++) {
                     num[i][j] = arr[j] - 48;
                     if (num[i][j] != 0)
                     row[i][num[i][j]] = col[j][num[i][j]] = g[(i / 3) * 3 + j / 3][num[i][j]] = 1;
                }
           }
           dfs(0);
     }
     return 0;
}

　　这题模型貌似很简单（我个人认为啊）