Problems

# Divisibility by 11

# Divisibility by 11

Divisibility by 11 is often stated as follows: add the digits standing separately at even and at odd positions. If the difference of these sums is divisible by 11, then the number is divisible by 11. Calculate the product of these sums.

## Input data

A positive integer n(10 ≤ n ≤ 2 \cdot 10^9).

## Output data

Print the product of sums of digits at even and at odd positions.

## Examples

Input example #1

27

Output example #1

14

Input example #2

2821

Output example #2

36

Input example #3

10001

Output example #3

0