import java.util.Scanner;

public class Main {

	private void solve() {
		Scanner in = new Scanner(System.in);
		int A = in.nextInt();
		int B = in.nextInt();
		int C = in.nextInt();
		
		int ans = C - (A - B) ;
		System.out.println((ans<0)?0:ans);
	}

	public static void main(String[] args) {
		new Main().solve();
	}
} import java.util.Scanner; Scanner java.util public class Main {

	private void solve() {
		Scanner in = new Scanner(System.in);
		int A = in.nextInt();
		int B = in.nextInt();
		int C = in.nextInt();
		
		int ans = C - (A - B) ;
		System.out.println((ans<0)?0:ans);
	}

	public static void main(String[] args) {
		new Main().solve();
	}
} Main private void solve() {
		Scanner in = new Scanner(System.in);
		int A = in.nextInt();
		int B = in.nextInt();
		int C = in.nextInt();
		
		int ans = C - (A - B) ;
		System.out.println((ans<0)?0:ans);
	} solve {
		Scanner in = new Scanner(System.in);
		int A = in.nextInt();
		int B = in.nextInt();
		int C = in.nextInt();
		
		int ans = C - (A - B) ;
		System.out.println((ans<0)?0:ans);
	} Scanner in = new Scanner(System.in); in new Scanner(System.in) int A = in.nextInt(); A in.nextInt() in.nextInt in int B = in.nextInt(); B in.nextInt() in.nextInt in int C = in.nextInt(); C in.nextInt() in.nextInt in int ans = C - (A - B) ; ans C - (A - B) C (A - B) A B System.out.println((ans<0)?0:ans) System.out.println System.out System System.out (ans<0)?0:ans (ans<0) ans 0 0 ans public static void main(String[] args) {
		new Main().solve();
	} main {
		new Main().solve();
	} new Main().solve() new Main().solve new Main() String[] args args public class Main {

	private void solve() {
		Scanner in = new Scanner(System.in);
		int A = in.nextInt();
		int B = in.nextInt();
		int C = in.nextInt();
		
		int ans = C - (A - B) ;
		System.out.println((ans<0)?0:ans);
	}

	public static void main(String[] args) {
		new Main().solve();
	}
} public class Main {

	private void solve() {
		Scanner in = new Scanner(System.in);
		int A = in.nextInt();
		int B = in.nextInt();
		int C = in.nextInt();
		
		int ans = C - (A - B) ;
		System.out.println((ans<0)?0:ans);
	}

	public static void main(String[] args) {
		new Main().solve();
	}
} Main
import java.util.Scanner;

public class Main {

	private void solve() {
		Scanner in = new Scanner(System.in);
		int A = in.nextInt();
		int B = in.nextInt();
		int C = in.nextInt();
		
		int ans = C - (A - B) ;
		System.out.println((ans<0)?0:ans);
	}

	public static void main(String[] args) {
		new Main().solve();
	}
}