import java.util.*;

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();
		boolean ans = C - (A - B) > 0;
		int value = C - (A - B);
		if(ans){
			System.out.println(value);
		}
		else{
			System.out.println(0);

		}
	}
} import java.util.*; util.* java 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();
		boolean ans = C - (A - B) > 0;
		int value = C - (A - B);
		if(ans){
			System.out.println(value);
		}
		else{
			System.out.println(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();
		boolean ans = C - (A - B) > 0;
		int value = C - (A - B);
		if(ans){
			System.out.println(value);
		}
		else{
			System.out.println(0);

		}
	} main {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		boolean ans = C - (A - B) > 0;
		int value = C - (A - B);
		if(ans){
			System.out.println(value);
		}
		else{
			System.out.println(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 boolean ans = C - (A - B) > 0; ans C - (A - B) > 0 C - (A - B) C (A - B) A B 0 int value = C - (A - B); value C - (A - B) C (A - B) A B if(ans){
			System.out.println(value);
		}
		else{
			System.out.println(0);

		} ans {
			System.out.println(value);
		} System.out.println(value) System.out.println System.out System System.out value {
			System.out.println(0);

		} System.out.println(0) System.out.println System.out System System.out 0 String[] args args
import java.util.*;

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();
		boolean ans = C - (A - B) > 0;
		int value = C - (A - B);
		if(ans){
			System.out.println(value);
		}
		else{
			System.out.println(0);

		}
	}
}
