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: Accepted)

<?php

$chars = array();

while (false !== ($chr = fgetc(STDIN))) {
    $code = ord(strtolower($chr));
    if ($code < ord('a') || ord('z') < $code) {
        continue;
    }

    if (! isset($chars[$code])) {
        $chars[$code] = 0;
    }

    $chars[$code] += 1;
}

for ($i = ord('a'); $i <= ord('z'); $i++) {
    $amount = isset($chars[$i]) ? $chars[$i] : 0;
    echo chr($i)." : $amount\n";
}