Poj 2676

最新推荐文章于 2018-12-11 17:06:46 发布

飞火恋月

最新推荐文章于 2018-12-11 17:06:46 发布

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分类专栏： POJ BFS&&DFS

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Sudoku

Time Limit: 2000MS		Memory Limit: 65536K
Total Submissions: 14480		Accepted: 7153		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

Sample Output

数独；

标记num这个数在第i行，第j列，第k个矩阵中有没有出现，不停地往下Dfs失败了就回溯；

#include <iostream>
#include <cstdio>
#include <cstring>

using namespace std;

int Map[10][10];
int row[10][10];//标记9行
int col[10][10];//标记9列
int grid[10][10];//标记9个9宫格

int getgrid(int x,int y){
    return 3*( x/3 )+(y/3);
}

int Dfs(int x,int y){


    if(x==10)
        return 1;
    int flag=0;

    if(Map[x][y]){
        if(y==9)
            flag=Dfs(x+1,1);
        else
            flag=Dfs(x,y+1);
        if(flag)
            return 1;
        else
            return 0;
    }

    int k=getgrid(x-1,y-1);

    for(int i=1;i<=9;i++){
        if(!Map[x][y]&&!col[y][i]&&!row[x][i]&&!grid[k][i]){
            Map[x][y]=i;
            col[y][i]=1;
            row[x][i]=1;
            grid[k][i]=1;

            if(y==9)
                flag=Dfs(x+1,1);
            else
                flag=Dfs(x,y+1);
            if(!flag){
                Map[x][y]=0;
                col[y][i]=0;
                row[x][i]=0;
                grid[k][i]=0;
            }
            else
                return 1;
        }
    }
    return 0;
}

int main(){
    int T;
    char str[10];
    scanf("%d",&T);
    while(T--){
        memset(Map,0,sizeof(Map));
        memset(row,0,sizeof(row));
        memset(col,0,sizeof(col));
        memset(grid,0,sizeof(grid));


        for(int i=1;i<=9;i++){
            scanf("%*c%s",str);
            for(int j=0;j<9;j++){
                Map[i][j+1]=str[j]-'0';
                int x=Map[i][j+1];
                if(x){
                    row[i][x]=1;
                    col[j+1][x]=1;
                    int k=getgrid(i-1,j);
                    grid[k][x]=1;
                }
            }
        }
        Dfs(1,1);
        for(int i=1;i<=9;i++){
            for(int j=1;j<=9;j++){
                cout<<Map[i][j];
            }
            cout<<endl;
        }
    }
    return 0;
}