#include <iostream>
using namespace std;

int main(){

	char ch;
	int counter[26] = {};

	while(cin >> ch){
		if(islower(ch)) counter[ch - 'a']++;
		if(isupper(ch)) counter[ch - 'A']++;
	}

	for(int i = 0; i < 26; i++){
		char ch2 = i + 'a';
		cout << ch2 << " : "<< counter[i] << endl;
	}

	return 0;
}