首页 > 代码库 > poj Sudoku（数独） DFS

poj Sudoku（数独） DFS

2024-07-15 07:39:58   221人阅读

Sudoku
Time Limit: 2000MS Memory Limit: 65536K
Total Submissions: 13665 Accepted: 6767 Special Judge

Description

Sudoku is a very simple task. A square table with 9 rows and 9 columns is divided to 9 smaller squares 3x3 as shown on the Figure. In some of the cells are written decimal digits from 1 to 9. The other cells are empty. The goal is to fill the empty cells with decimal digits from 1 to 9, one digit per cell, in such way that in each row, in each column and in each marked 3x3 subsquare, all the digits from 1 to 9 to appear. Write a program to solve a given Sudoku-task.

Input

The input data will start with the number of the test cases. For each test case, 9 lines follow, corresponding to the rows of the table. On each line a string of exactly 9 decimal digits is given, corresponding to the cells in this line. If a cell is empty it is represented by 0.

Output

For each test case your program should print the solution in the same format as the input data. The empty cells have to be filled according to the rules. If solutions is not unique, then the program may print any one of them.

Sample Input

1103000509002109400000704000300502006060000050700803004000401000009205800804000107

Sample Output

143628579572139468986754231391542786468917352725863914237481695619275843854396127
讲解：游戏都玩过，但就是基本上见过没做出来过，哈哈、、、挺有意思的代码，题意都知道，关键就是如何进行搜索，其实就是不断地进行枚举，如果满足所有的条件就跳出来；
AC代码：
 1 #include<iostream> 2 #include<algorithm> 3 #include<cstdio> 4 #include<cstring> 5 using namespace std; 6 const int N = 11; 7 int Map[N][N], flag; 8 char MAp[N][N]; 9 int check(int ans,int key)10 {11     int x = (key-1)/9+1;12     int y =  key-(x-1)*9;13     for(int i=1; i<=9; i++)//行是否冲突14        if(Map[x][i] == ans)15             return 0;16     for(int i=1; i<=9; i++) //列是否冲突17        if(Map[i][y] == ans)18            return 0;19            if(x<=3)x = 1; //x所在小九格起点20            if(x>3 && x<7)x=4;21            if(x>=7) x=7;22            if(y<=3) y = 1; //y所在小九格起点23            if(y>3 && y<7) y=4;24            if(y>=7) y=7;25     for(int i=0; i<3; i++) //小的九格是否冲突26        for(int j=0; j<3; j++)27             if(Map[x+i][y+j] == ans)28                     return 0;29   return 1;//以上条件都不符合，返回1；30 }31 int dfs(int key)32 {33     int x = (key-1)/9+1;34     int y =  key-(x-1)*9;35     if(key>81)36     {37         flag = 1;38         return 0;39     }40     if(Map[x][y]!=0)//不是0，直接跳过去41     {42         dfs(key+1);43     }44     else //否者，在这个位置枚举九个数，进行递归搜索45     {46     for(int k=1; k<=9; k++)47         if(check(k,key))48             {49                 Map[x][y] = k;50                 dfs(key+1);51                 if(flag == 1)  return 0;52                 Map[x][y] = 0;53             }54     }55     return 0;56 }57 int main()58 {59     int T,i,j;60 //    freopen("in2.txt","r",stdin);61 //    freopen("out2.txt","w",stdout);62     scanf("%d",&T);63     while(T--)64     {65         memset(Map,0,sizeof(Map));66        for(i=1; i<=9; i++)67           for(j=1; j<=9; j++)68           {69              cin>>MAp[i][j];70              Map[i][j] = MAp[i][j]-‘0‘;71           }72              flag = 0;73               dfs(1);74        for(i=1; i<=9; i++)75        {76           for(j=1; j<=9; j++)77              printf("%d",Map[i][j]);78              printf("\n");79        }80     }81     return 0;82 }

 


联系
我们