[UVa] 11520 Fill the Square.cpp

#include <cstdio>
using namespace std;

char square[12][12];

void Fill (int n,int i,int j){
    char filled = 'A';
    bool up,left,right,down;
    while (filled <= 'Z'){
        if (i-1<0  || square[i-1][j]!=filled) up=1;   else up=0;
        if (i+1>=n || square[i+1][j]!=filled) down=1; else down=0;
        if (j-1<0  || square[i][j-1]!=filled) left=1; else left=0;
        if (j+1>=n || square[i][j+1]!=filled) right=1;else right=0;

        if (up && down && left && right){
            square[i][j] = filled;
            printf("%c",filled);
            break;
        }
        else filled += 1;
    }
}

int main()
{
    int t,n,Case=1;
    scanf("%d",&t);
    while (t--)
    {
        scanf("%d",&n);
        gets(square[0]);
        for(int i=0;i<n;i++) gets(square[i]);

        printf("Case %d:\n",Case++);

        for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                if (square[i][j]!='.')
                    printf("%c",square[i][j]);
                else Fill(n,i,j);
            }
            printf("\n");
        }
    }

    return 0;
}