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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<bits/stdc++.h>
using namespace std;
#define rkc ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
typedef long long ll;
#define fl(i,a,b) for(ll i=a;i<b;i++)
#define rfl(i,a,b) for(ll i=a;i>b;i--)
#define pb push_back
#define mp make_pair
#define test ll t;cin>>t;while(t--)
#define lld long double
#define vpp vector<pair<ll,ll>>
#define ff first
#define ss second
const ll M = 1e9 + 7;
const double pi  =3.141592653589793238463;
int main()
{
    rkc;
    ll a,b,c;
    cin>>a>>b>>c;
    if(c<=a-b)cout<<0;
    else cout<<c-a+b;
}