[UVa] 414 Machined Surfaces.cpp

#include <cstdio>
using namespace std;
int main()
{
//    freopen ("input.txt","rt",stdin);
    int N;
    while (scanf("%d",&N)){
        if (!N) break;
        int nOfX[20]={0},Max = 0;
        char line[30];
        gets(line);
        for (int i=0; i<N; i++){
            gets(line);
            for (int j=0; line[j]; j++)
                if (line[j]=='X') nOfX[i]++;
            if (nOfX[i]>Max)
                Max = nOfX[i];
        }
        int ans = 0;
        for (int i=0; i<N; i++)
            ans += (Max-nOfX[i]);
        printf("%d\n",ans);
    }
    return 0;
}