Given a natural number N as the parameter, write a function solution to return the sum of each digit of N.
For example, if N = 123, return 1 + 2 + 3 = 6.

Constraints

• Range of N : natural number less than or equal to 100,000,000.

Examples

Example #1
Same as the example in the problem statement.

Example #2
Since 9 + 8 + 7 = 24, return 24.