Problem:
Score : 100 points

Problem Statement

We have two bottles for holding water.

Bottle 1 can hold up to A milliliters of water, and now it contains B milliliters of water.

Bottle 2 contains C milliliters of water.

We will transfer water from Bottle 2 to Bottle 1 as much as possible.

How much amount of water will remain in Bottle 2?

Constraints

All values in input are integers.

1 \leq B \leq A \leq 20

1 \leq C \leq 20

Input

Input is given from Standard Input in the following format:

A B C

Output

Print the integer representing the amount of water, in milliliters, that will remain in Bottle 2.

Sample Input 1

6 4 3

Sample Output 1

1

We will transfer two milliliters of water from Bottle 2 to Bottle 1, and one milliliter of water will remain in Bottle 2.

Sample Input 2

8 3 9

Sample Output 2

4

Sample Input 3

12 3 7

Sample Output 3

0

Solution in Python (3.4.3) (judge verdict: Accepted)

from collections import defaultdict, deque
import sys

sys.setrecursionlimit(100000)

MIN = -10 ** 9
MAX = 10 ** 9 + 7


def main():
    # N = int(input())
    a, b, c = [int(a) for a in input().split()]
    # # A = [
    # #     int(input())
    # #     for _ in range(N)
    # # ]
    # A = [int(a) for a in input().split()]

    print(max(0,c - a + b))


if __name__ == '__main__':
    main()