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: Runtime Error)


#N = int(input())
N = 30

min_num = N
for a in range(1,N/2):
    b = N-a
    str_num_arr = list(str(a))
    sum_A = sum(map(int, str_num_arr))

    str_num_arr = list(str(b))
    sum_B = sum(map(int, str_num_arr))

    sum_all = sum_A+sum_B
    if min_num > sum_all:
        min_num = sum_all

print(min_num)