import std.stdio;
import std.conv;
import std.array;
import std.string;

void main()
{
  string s, str = "";
  while ((s = readln()).length) {
    str ~= s;
  }

  for (int i = 0; i < 26; i++) {
    int cnt;
    
    cnt += str.count('a' + i);
    cnt += str.count('A' + i);
    writeln(to!char('a' + i), " : ", cnt);
  }
}