process.stdin.resume();
process.stdin.setEncoding('utf8');
process.stdin.on('data', function (chunk)
{
  var text = chunk.trim();
  var x = [];
  for (var i = 97; i <= 122; i++) {
    x[String.fromCharCode(i)] = 0; 
  }

  for (i = 0; i < text.length; i++) {
    var c = text.charAt(i).toLowerCase();
    var cCode = c.charCodeAt(0);
    if (cCode >= 97 && cCode < 123) {
      x[c] += 1;
    }
  }

  for (var i =97; i <=122; i++) {
    console.log(String.fromCharCode(i), ":", x[String.fromCharCode(i)]);
  }
});