UVA 11520 填充正方形

https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=2515

http://7xjob4.com1.z0.glb.clouddn.com/c6a2a6f54f5a6c2cae2c82df2ec552f7

题意：填已有字母的格子，使相邻格子字母不同，使字典序尽量小

思路：从小到大排，检验是否可行

#include <bits/stdc++.h>
using namespace std;

int n;
char grid[15][15];

int main()
{
    int T,i,j,cas=1;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d",&n);
        for(i=0;i<n;i++)
        {
            scanf("%s",grid[i]);
        }
        for(i=0;i<n;i++)
        {
            for(j=0;j<n;j++)
            {
                if(grid[i][j]=='.')
                {
                    for(char ch='A';ch<='Z';ch++)
                    {
                        bool flg=true;
                        if(i-1>=0 && grid[i-1][j]==ch)  flg=false;
                        if(i+1<n && grid[i+1][j]==ch)   flg=false;
                        if(j-1>=0 && grid[i][j-1]==ch)  flg=false;
                        if(j+1<n && grid[i][j+1]==ch)   flg=false;
                        if(flg)
                        {
                            grid[i][j]=ch;
                            break;
                        }
                    }
                }
            }
        }

        printf("Case %d:
",cas++);
        for(i=0;i<n;i++)
        {
            printf("%s
",grid[i]);
        }
    }
    return 0;
}