Problem Statement

You are given two positive integers a and b.
Let x be the average of a and b.
Print x rounded up to the nearest integer.

Input

Input is given from Standard Input in the following format:
a b

Output

Print x rounded up to the nearest integer.

Constraints

• a and b are integers.
• $1 \leq a, b \leq 100$

Sample Input 1

1 3

Sample Output 1

2

The average of 1 and 3 is 2.0, and it will be rounded up to the nearest integer, 2.

Sample Input 2

7 4

Sample Output 2

6

The average of 7 and 4 is 5.5, and it will be rounded up to the nearest integer, 6.

Sample Input 3

5 5

Sample Output 3

5

见题面 Input 部分

见题面 Output 部分