#494. While: number of even digits
You get a positive integer n. Use a `while` loop to find its **number of even digits**.
### Input
One integer n (1 ≤ n ≤ 10⁹).
### Output
The answer.
Examples
Input
216231249
Output
5
Input
119
Output
0
💡 You can solve it with Python, JavaScript or blocks. Read the input line by line with input(). Don't print a question (like input("Number: ")). Print exactly what the output asks for, nothing more.