Competitions

# Lesson 4. September 24 - 30. Loops: while statement

# 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

A positive integer **n** (**10** ≤ **n** ≤ **2** *`10`

).^{9}

#### Output

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

Input example #1

27

Output example #1

14

Input example #2

2821

Output example #2

36

Input example #3

10001

Output example #3

0