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 <string>
#include <queue>
#include <stack>
#include <vector>
#include <sstream>
#include <algorithm>
#include <deque>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <list>
#include <cstdio>
#include <iostream>
#include <cmath>
#include <climits>
#include <bitset>
#include <functional>
#include <numeric>
#include <ctime>
#include <cassert>
#include <cstring>
#include <fstream>

using namespace std;

#define FOR(i, a, b) for(int (i)=(a);(i)<(b);(i)++)
#define IFOR(i, a, b) for(int (i)=(a);(i)<=(b);(i)++)
#define RFOR(i, a, b) for(int (i)=(a);(i)>=(b);(i)--)
#define REP(i, n) FOR((i), 0, (n))

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

template<class T>
void print_container(T &container, string delim=" ") {
    bool first = true;
    for(auto &t: container){
        if(!first){
            cout << delim;
        }
        first = false;
        cout << t;
    }
    cout << endl;
}

int main() {
    int a, b, c;
    cin >> a >> b >> c;
    cout << max(0, c-(a-b)) << endl;
    return 0;
}