import java.io.InputStream;
import java.io.PrintStream;
import java.util.Scanner;

public class Main {
	InputStream in = System.in;
	PrintStream out = System.out;

	public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();

		sc.close();

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

	}

	public static void main(String[] args) {
		new Main()._main(args);
	}
} import java.io.InputStream; InputStream java.io import java.io.PrintStream; PrintStream java.io import java.util.Scanner; Scanner java.util public class Main {
	InputStream in = System.in;
	PrintStream out = System.out;

	public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();

		sc.close();

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

	}

	public static void main(String[] args) {
		new Main()._main(args);
	}
} Main InputStream in = System.in; in System.in System System.in PrintStream out = System.out; out System.out System System.out public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();

		sc.close();

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

	} _main {
		Scanner sc = new Scanner(in);

		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();

		sc.close();

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

	} Scanner sc = new Scanner(in); sc new Scanner(in) int A = sc.nextInt(); A sc.nextInt() sc.nextInt sc int B = sc.nextInt(); B sc.nextInt() sc.nextInt sc int C = sc.nextInt(); C sc.nextInt() sc.nextInt sc sc.close() sc.close sc out.println(Math.max(0, C - (A - B))) out.println out Math.max(0, C - (A - B)) Math.max Math 0 C - (A - B) C (A - B) A B String[] args args public static void main(String[] args) {
		new Main()._main(args);
	} main {
		new Main()._main(args);
	} new Main()._main(args) new Main()._main new Main() args String[] args args public class Main {
	InputStream in = System.in;
	PrintStream out = System.out;

	public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();

		sc.close();

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

	}

	public static void main(String[] args) {
		new Main()._main(args);
	}
} public class Main {
	InputStream in = System.in;
	PrintStream out = System.out;

	public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();

		sc.close();

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

	}

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

public class Main {
	InputStream in = System.in;
	PrintStream out = System.out;

	public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();

		sc.close();

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

	}

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