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 PHP7 (7.0.15) (judge verdict: Runtime Error)

<?php
  
  $sc = new Scanner();
　$A = $sc->nextInt(); // 高橋くんの試合数
  $B = $sc->nextInt(); // 高橋くんの勝利数
  $C = $sc->nextInt(); // 青木くんの試合数


  $transferA = $A - $B; // 高橋くんの勝率
  $transferB = $transferA - $C;

// どっちが勝率が高いか
	echo $transferB;