Score : 100 points

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.

Constraints

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

Input

Input is given from Standard Input in the following format:

a b

Output

Print x rounded up to the nearest integer.


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