Problem:
Score : 100 points

Problem Statement

You are given an integer N that has exactly four digits in base ten.
How many times does 2 occur in the base-ten representation of N?

Constraints

1000 \leq N \leq 9999

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer.

Sample Input 1

1222

Sample Output 1

3

2 occurs three times in 1222. By the way, this contest is held on December 22 (JST).

Sample Input 2

3456

Sample Output 2

0

Sample Input 3

9592

Sample Output 3

1

Solution in Ruby (2.3.3) (judge verdict: Runtime Error)

a = gets.chomp.to_i
b = []
a.times do
 b.push(gets.chomp.to_i)
end
b.sort!
(a-1).times do
b = b.map{|aa|aa-b[0]}
b.delete_at(0)
if b.size == 1 || b.size == 0
  break
end
end
if b[0] % 2 == 0
  puts "second"
else
   puts "first"
end