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: Runtime Error)

n = int(input())
if n < 10:
  print(n)
  exit()
if n >= 10 and n < 100:
  print(9)

if n >= 100 and n < 1000:
  #print(9 + (int(str(n)[-2:])) + 1)
  print(9 + (n-100) + 1)
  exit()
if n >= 1000 and n < 10000:
  print(909)
  exit()
if n >= 10000 and n < 100000:
  print(909 + (n-10000) + 1)
  exit
if n == 100000:
  print(90909)