Problem:
Counting Characters

Write a program which counts and reports the number of each alphabetical letter. Ignore the case of characters.

Input

A sentence in English is given in several lines.

Output

Prints the number of alphabetical letters in the following format:

a : The number of 'a'
b : The number of 'b'
c : The number of 'c'
.
.
z : The number of 'z'

Constraints

The number of characters in the sentence < 1200

Sample Input

This is a pen.

Sample Output

a : 1
b : 0
c : 0
d : 0
e : 1
f : 0
g : 0
h : 1
i : 2
j : 0
k : 0
l : 0
m : 0
n : 1
o : 0
p : 1
q : 0
r : 0
s : 2
t : 1
u : 0
v : 0
w : 0
x : 0
y : 0
z : 0

Solution in PHP (judge verdict: Wrong Answer)

<?php

$input = trim(fgets(STDIN));

$alphabet = array_fill_keys(range('a', 'z'), 0);
foreach (str_split($input) as $c) {
    if (! ctype_alpha($c)) { continue; }

    $alphabet[strtolower($c)]++;
}

foreach ($alphabet as $char => $count) {
    printf('%s : %d%s', $char, $count, PHP_EOL);
}