import java.io.*;

public class Main {

	final static long MOD = 1000000007;
	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] Ws = W.split(" ");
		int A = Integer.parseInt(Ws[0]);
		int B = Integer.parseInt(Ws[1]);
		int C = Integer.parseInt(Ws[2]);

		System.out.println(Math.max(C-(A-B),0));

	}

} import java.io.*; io.* java public class Main {

	final static long MOD = 1000000007;
	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] Ws = W.split(" ");
		int A = Integer.parseInt(Ws[0]);
		int B = Integer.parseInt(Ws[1]);
		int C = Integer.parseInt(Ws[2]);

		System.out.println(Math.max(C-(A-B),0));

	}

} Main final static long MOD = 1000000007; MOD 1000000007 public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] Ws = W.split(" ");
		int A = Integer.parseInt(Ws[0]);
		int B = Integer.parseInt(Ws[1]);
		int C = Integer.parseInt(Ws[2]);

		System.out.println(Math.max(C-(A-B),0));

	} main {
		// TODO 自動生成されたメソッド・スタブ

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] Ws = W.split(" ");
		int A = Integer.parseInt(Ws[0]);
		int B = Integer.parseInt(Ws[1]);
		int C = Integer.parseInt(Ws[2]);

		System.out.println(Math.max(C-(A-B),0));

	} BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); in new BufferedReader(new InputStreamReader(System.in)) String W = in.readLine(); W in.readLine() in.readLine in String[] Ws = W.split(" "); Ws W.split(" ") W.split W " " int A = Integer.parseInt(Ws[0]); A Integer.parseInt(Ws[0]) Integer.parseInt Integer Ws[0] Ws 0 int B = Integer.parseInt(Ws[1]); B Integer.parseInt(Ws[1]) Integer.parseInt Integer Ws[1] Ws 1 int C = Integer.parseInt(Ws[2]); C Integer.parseInt(Ws[2]) Integer.parseInt Integer Ws[2] Ws 2 System.out.println(Math.max(C-(A-B),0)) System.out.println System.out System System.out Math.max(C-(A-B),0) Math.max Math C-(A-B) C (A-B) A B 0 String[] args args public class Main {

	final static long MOD = 1000000007;
	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] Ws = W.split(" ");
		int A = Integer.parseInt(Ws[0]);
		int B = Integer.parseInt(Ws[1]);
		int C = Integer.parseInt(Ws[2]);

		System.out.println(Math.max(C-(A-B),0));

	}

} public class Main {

	final static long MOD = 1000000007;
	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] Ws = W.split(" ");
		int A = Integer.parseInt(Ws[0]);
		int B = Integer.parseInt(Ws[1]);
		int C = Integer.parseInt(Ws[2]);

		System.out.println(Math.max(C-(A-B),0));

	}

} Main
import java.io.*;

public class Main {

	final static long MOD = 1000000007;
	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] Ws = W.split(" ");
		int A = Integer.parseInt(Ws[0]);
		int B = Integer.parseInt(Ws[1]);
		int C = Integer.parseInt(Ws[2]);

		System.out.println(Math.max(C-(A-B),0));

	}

}
