#include<iostream>
#include<cstdio>
#include<cctype>

using namespace std;
int main() {
	char ch;
	int cnt[26] = {};

	while (cin >> ch) {
		ch = tolower(ch);
		if (isalpha(ch)) {
			cnt[ch - 'a']++;
		}
	}

	for (int i = 0; i < 26; i++) {
		cout << (char)(i+'a') << " : " << cnt[i] << endl;
	}

	return 0;
}