Problem Description

This is the $23$rd AtCoder Beginner Contest. This contest is held in May.

Takahashi noticed that when he splits the integer $23$ into its tens and ones place and adds them together, he gets $2 + 3 = 5$, which is equal to the current month.

Fascinated by this, Takahashi decided to calculate the sum of the digits of a two-digit positive integer $X$ he had on hand.

Your task is to find the sum of the digits of the positive integer $X$.

Input Format

The input is given from the standard input in the following format:

$ X $

• The first line contains a two-digit positive integer $X$ $(10 ≦ X ≦ 99)$.

Output Format

Output the sum of the digits of the positive integer $X$ in one line. Make sure to include a newline at the end of the output.

Sample Input and Output

Sample Input #1

23

Sample Output #1

5

Sample Input #2

70

Sample Output #2

7

Sample Input #3

99

Sample Output #3

18

Notes/Hints

Sample Explanation 1

• As explained in the problem statement, $2 + 3 = 5$.

Sample Explanation 2

• The ones place can be $0$.

见题面 Input 部分

见题面 Output 部分