#include<bits/stdc++.h>
using namespace std;
int main(){
    int alp[26]={};
    char al;
    while(cin >> al){
        al = tolower(al);
        int num = al-'a';
        alp[num]++;

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