import java.io.PrintWriter;
import java.util.*;

public class Main {
		public static void main(String[] args) {
			Scanner stdin = new Scanner(System.in);
			PrintWriter out = new PrintWriter(System.out);
			
			int A = Integer.parseInt(stdin.next());
			int B = Integer.parseInt(stdin.next());
			int C = Integer.parseInt(stdin.next());

			if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			}
			
			out.flush();
	}
}

 import java.io.PrintWriter; PrintWriter java.io import java.util.*; util.* java public class Main {
		public static void main(String[] args) {
			Scanner stdin = new Scanner(System.in);
			PrintWriter out = new PrintWriter(System.out);
			
			int A = Integer.parseInt(stdin.next());
			int B = Integer.parseInt(stdin.next());
			int C = Integer.parseInt(stdin.next());

			if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			}
			
			out.flush();
	}
} Main public static void main(String[] args) {
			Scanner stdin = new Scanner(System.in);
			PrintWriter out = new PrintWriter(System.out);
			
			int A = Integer.parseInt(stdin.next());
			int B = Integer.parseInt(stdin.next());
			int C = Integer.parseInt(stdin.next());

			if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			}
			
			out.flush();
	} main {
			Scanner stdin = new Scanner(System.in);
			PrintWriter out = new PrintWriter(System.out);
			
			int A = Integer.parseInt(stdin.next());
			int B = Integer.parseInt(stdin.next());
			int C = Integer.parseInt(stdin.next());

			if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			}
			
			out.flush();
	} Scanner stdin = new Scanner(System.in); stdin new Scanner(System.in) PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) int A = Integer.parseInt(stdin.next()); A Integer.parseInt(stdin.next()) Integer.parseInt Integer stdin.next() stdin.next stdin int B = Integer.parseInt(stdin.next()); B Integer.parseInt(stdin.next()) Integer.parseInt Integer stdin.next() stdin.next stdin int C = Integer.parseInt(stdin.next()); C Integer.parseInt(stdin.next()) Integer.parseInt Integer stdin.next() stdin.next stdin if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			} C-(A-B)<0 C-(A-B) C (A-B) A B 0 {
				System.out.println(0);
			} System.out.println(0) System.out.println System.out System System.out 0 {
			System.out.println(C-(A-B));
			} System.out.println(C-(A-B)) System.out.println System.out System System.out C-(A-B) C (A-B) A B out.flush() out.flush out String[] args args public class Main {
		public static void main(String[] args) {
			Scanner stdin = new Scanner(System.in);
			PrintWriter out = new PrintWriter(System.out);
			
			int A = Integer.parseInt(stdin.next());
			int B = Integer.parseInt(stdin.next());
			int C = Integer.parseInt(stdin.next());

			if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			}
			
			out.flush();
	}
} public class Main {
		public static void main(String[] args) {
			Scanner stdin = new Scanner(System.in);
			PrintWriter out = new PrintWriter(System.out);
			
			int A = Integer.parseInt(stdin.next());
			int B = Integer.parseInt(stdin.next());
			int C = Integer.parseInt(stdin.next());

			if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			}
			
			out.flush();
	}
} Main
import java.io.PrintWriter;
import java.util.*;

public class Main {
		public static void main(String[] args) {
			Scanner stdin = new Scanner(System.in);
			PrintWriter out = new PrintWriter(System.out);
			
			int A = Integer.parseInt(stdin.next());
			int B = Integer.parseInt(stdin.next());
			int C = Integer.parseInt(stdin.next());

			if(C-(A-B)<0) {
				System.out.println(0);
			}
			else {
			System.out.println(C-(A-B));
			}
			
			out.flush();
	}
}


