Alice and Brown are brothers in a family and each receives pocket money in celebration of the coming year. They are very close and share the total amount of the money fifty-fifty. The pocket money each receives is a multiple of 1,000 yen.
Write a program to calculate each one’s share given the amount of money Alice and Brown received.
The input is given in the following format.
a b
A line of data is given that contains two values of money: a (1000 ≤ a ≤ 50000) for Alice and
Output the amount of money each of Alice and Brown receive in a line.
1000 3000
2000
5000 5000
5000
1000 2000
1500