Mystery Event

bj12z_jiasiyuan observed three archers A, B, and C who hit x, y, and z rings respectively. A "mysterious event" occurs if the number of rings hit by one person is greater than the sum of the rings hit by the other two.

Your task is to determine how many mysterious events occur.

inputFormat

A single line containing three space-separated integers x, y, and z representing the number of rings hit by archers A, B, and C respectively.

outputFormat

Output a single integer representing the total number of mysterious events.

sample

12 3 5

1