Sum of Digits
Given an integer, print the sum of its digits.
Input
A single line containing an integer n (can be negative) with at most 19 digits, not counting the minus sign.
Output
The sum of the digits of n. If n is negative, ignore the minus sign.
Examples
Input: 1234
Output: 10
Input: -56
Output: 11
Input: 0
Output: 0
Input: 100
Output: 1
The zeros in 100 don't add anything to the sum. Only the 1 counts.