#include<iostream>
using namespace std;

int main(){
	int num;
 	int counter[26] = {0};
	char ch, ch2, ch3; 
	
	
	while ( cin >> ch ){
		ch2 = tolower(ch);
		num = ch2 - 'a';
		
		counter[num]++;
	}
    
	for(int i=0; i<26; i++){
		ch3 = 'a' + i;
		cout << ch3 <<" : " << counter[i] << endl;
	}
	return 0;	
}