【POJ 2676】 Sudoku

【题目链接】

http://poj.org/problem?id=2676

【算法】

深度优先搜索

【代码】

#include <algorithm>
#include <bitset>
#include <cctype>
#include <cerrno>
#include <clocale>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <limits>
#include <list>
#include <map>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <utility>
#include <vector>
#include <cwchar>
#include <cwctype>
#include <stack>
#include <limits.h>
using namespace std;

struct info
{
        int x,y;
} pos[];

int i,j,len,T;
char mp[][];
bool row[][],col[][],grid[][];
bool solved;

inline int getpos(int x,int y)
{
        return (x - ) /  *  + (y - ) /  + ;
}
inline void dfs(int dep)
{
        int i;
        if (dep > len)
        {
                solved = true;
                return;
        }
        for (i = ; i <= ; i++)
        {
                if (!row[pos[dep].x][i] && !col[pos[dep].y][i] && !grid[getpos(pos[dep].x,pos[dep].y)][i])
                {
                        mp[pos[dep].x][pos[dep].y] = i + '';
                        row[pos[dep].x][i] = true;
                        col[pos[dep].y][i] = true;
                        grid[getpos(pos[dep].x,pos[dep].y)][i] = true;
                        dfs(dep+);
                        if (solved) return;
                        row[pos[dep].x][i] = false;
                        col[pos[dep].y][i] = false;
                        grid[getpos(pos[dep].x,pos[dep].y)][i] = false;
                }
        }
}

int main()
{

        scanf("%d",&T);
        getchar();
        while (T--)
        {
                solved = false;
                memset(row,false,sizeof(row));
                memset(col,false,sizeof(col));
                memset(grid,false,sizeof(grid));
                len = ;
                for (i = ; i <= ; i++)
                {
                        for (j = ; j <= ; j++)
                        {
                                mp[i][j] = getchar();
                                if (mp[i][j] == '') pos[++len] = (info){i,j};
                                else
                                {
                                        row[i][mp[i][j]-''] = true;
                                        col[j][mp[i][j]-''] = true;
                                        grid[getpos(i,j)][mp[i][j]-''] = true;
                                }
                        }
                        getchar();
                }
                dfs();
                for (i = ; i <= ; i++)
                {
                        for (j = ; j <= ; j++)
                        {
                                printf("%c",mp[i][j]);
                        }
                        printf("\n");
                }
        }

        return ;

}