Background

Description

Given a non-negative int n, return the sum of its digits recursively (no loops). Note that mod (%) by 10 yields the rightmost digit (126 % 10 is 6), while divide (/) by 10 removes the rightmost digit (126 / 10 is 12).

Format

Input

Output

Samples

126

9

49

13

12

3

Limitation

1s, 1024KiB for each test case.