UVa 11577 - Letter Frequency

#include <algorithm>
#include <iostream>
#include <cstdlib>
#include <cstring>
#include <cstdio>
#include <cmath>

using namespace std;

int main()
{
	int  n,count[27];
	char buf[202];
	while (~scanf("%d",&n)) {
		getchar();
		while (n --) {
			gets(buf);
			for (int i = 0; i < 27; ++ i)
				count[i] = 0;
			for (int i = 0; buf[i]; ++ i) {
				if (buf[i] >= 'A' && buf[i] <= 'Z')
					++ count[buf[i]-'A'];
				if (buf[i] >= 'a' && buf[i] <= 'z')
					++ count[buf[i]-'a'];
			}
			int max = 0;
			for (int i = 0; i < 27; ++ i)
				if (max < count[i])
					max = count[i];
			for (int i = 0; i < 27; ++ i)
				if (max == count[i])
					printf("%c",'a'+i);
			printf("\n");
		}
	}
    return 0;
}