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 Python3 (judge verdict: Accepted)

str = ""
upperStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
lowerStr = "abcdefghijklmnopqrstuvwxyz"
count = [0] * 26

while True:
        try:
                str += input()
        except:
                break

for n in range(len(str)):
        for i in range(26):
                if str[n] == upperStr[i] or str[n] == lowerStr[i]:
                        count[i] += 1
                        break

for i in range(26):
        print(lowerStr[i], ":", count[i])