import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		sc.close();
		int D = C-(A-B);
		System.out.println(D>0?D:0);
	}

} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		sc.close();
		int D = C-(A-B);
		System.out.println(D>0?D:0);
	}

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

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		sc.close();
		int D = C-(A-B);
		System.out.println(D>0?D:0);
	}

} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		sc.close();
		int D = C-(A-B);
		System.out.println(D>0?D:0);
	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		sc.close();
		int D = C-(A-B);
		System.out.println(D>0?D:0);
	}

}