#include <bits/stdc++.h>
using namespace std;

int main() {
  char ch;
  int a[26] = {};
  
  while (cin >> ch) {
    ch = tolower(ch);
    if (isalpha(ch)) a[ch - 'a']++;
  }
  for (int i = 0; i < 26; i++) {
    cout << (char)( i + 'a') << " : " << a[i] << endl;
  }
}

