Problem:
Score : 200 points

Problem Statement

Takahashi has two positive integers A and B.

It is known that A plus B equals N.
Find the minimum possible value of "the sum of the digits of A" plus "the sum of the digits of B" (in base 10).

Constraints

2 ≤ N ≤ 10^5

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

Print the minimum possible value of "the sum of the digits of A" plus "the sum of the digits of B".

Sample Input 1

15

Sample Output 1

6

When A=2 and B=13, the sums of their digits are 2 and 4, which minimizes the value in question.

Sample Input 2

100000

Sample Output 2

10

Solution in Python (3.4.3) (judge verdict: Accepted)

N=int(input())

import numpy as np

a=np.arange(N)
a=np.delete(a,0)

b=N-a

num_arr=[]

for i in range(len(a)):
	factor_a=[int(x) for x in list(str(a[i]))]
	factor_b=[int(x) for x in list(str(b[i]))]
	num_arr.append(sum(factor_a)+sum(factor_b))

print(min(num_arr))