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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;

namespace debug
{
    public static partial class Program
    {
        public static void Main()
        {
            var abc = Console.ReadLine().ToLongArray();
            Console.WriteLine(Math.Max(abc[2] - (abc[0] - abc[1]), 0));
        }
    }

    public static partial class Program
    {
        //テンプレここから
        private static long Gcd(long aaa, long bbb) => bbb == 0 ? aaa : Gcd(bbb, aaa % bbb);
        private static long Lcm(long aaa, long bbb) => aaa * bbb / Gcd(aaa, bbb);
        private static long ToLong(this double ddd) => (long) ddd;
        private static long ToLong(this string str) => long.Parse(str);
        private static long[] ToLong(this IEnumerable<string> strs) => strs.Select(x => x.ToLong()).ToArray();
        private static long[] ToLongArray(this string str, char opr = ' ') => str.Split(opr).ToLong();
        private static long Diff(long aaa, long bbb) => Math.Abs(Math.Max(aaa, bbb) - Math.Min(aaa, bbb));
        private static long Sign(this long iii) => Math.Sign(iii);
        private static bool IsEven(this long iii) => iii % 2 == 0;
        private static bool IsEven(this int iii) => iii % 2 == 0;

        private static readonly int[] Dx =
        {
            0, -1, 0, 1
        };

        private static readonly int[] Dy =
        {
            -1, 0, 1, 0
        };

        public const int Mod = 1000000007;
        public const string UpperAlphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        public const string LowerAlphabet = "abcdefghijklmnopqrstuvwxyz";
        private static long ToLong(this char ccc) => ccc.ToString().ToLong();
        private static string Join(this IEnumerable<string> array, string sep = "") => string.Join(sep, array);
        private static string Join(this IEnumerable<char> array, string sep = "") => string.Join(sep, array);

        private static string JoinToStr(this IEnumerable<long> array, string sep = "") =>
            array.Select(xxx => xxx.ToString()).Join(sep);

        public static string JoinToStr(this IEnumerable<int> array, string sep = "") =>
            array.Select(xxx => xxx.ToString()).Join(sep);

        //テンプレここまで
    }
}