import 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 res = Math.max(C-(A-B), 0);
		
		System.out.println(res);
		
	}
	
} import java.util.*; util.* java 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 res = Math.max(C-(A-B), 0);
		
		System.out.println(res);
		
	}
	
} 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 res = Math.max(C-(A-B), 0);
		
		System.out.println(res);
		
	} main {		
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		sc.close();
		
		int res = Math.max(C-(A-B), 0);
		
		System.out.println(res);
		
	} 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 res = Math.max(C-(A-B), 0); res Math.max(C-(A-B), 0) Math.max Math C-(A-B) C (A-B) A B 0 System.out.println(res) System.out.println System.out System System.out res 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 res = Math.max(C-(A-B), 0);
		
		System.out.println(res);
		
	}
	
} 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 res = Math.max(C-(A-B), 0);
		
		System.out.println(res);
		
	}
	
} Main
import 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 res = Math.max(C-(A-B), 0);
		
		System.out.println(res);
		
	}
	
}