import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		// 整数の入力
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		int empty = A - B;
		int ret = C- empty;
		if(ret < 0){
			ret = 0;
		}
		System.out.println(ret);

		sc.close();
	}
} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		// 整数の入力
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		int empty = A - B;
		int ret = C- empty;
		if(ret < 0){
			ret = 0;
		}
		System.out.println(ret);

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

		// 整数の入力
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		int empty = A - B;
		int ret = C- empty;
		if(ret < 0){
			ret = 0;
		}
		System.out.println(ret);

		sc.close();
	} main {
		Scanner sc = new Scanner(System.in);

		// 整数の入力
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		int empty = A - B;
		int ret = C- empty;
		if(ret < 0){
			ret = 0;
		}
		System.out.println(ret);

		sc.close();
	} 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 int empty = A - B; empty A - B A B int ret = C- empty; ret C- empty C empty if(ret < 0){
			ret = 0;
		} ret < 0 ret 0 {
			ret = 0;
		} ret = 0 ret 0 System.out.println(ret) System.out.println System.out System System.out ret sc.close() sc.close sc String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		// 整数の入力
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		int empty = A - B;
		int ret = C- empty;
		if(ret < 0){
			ret = 0;
		}
		System.out.println(ret);

		sc.close();
	}
} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		// 整数の入力
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		int empty = A - B;
		int ret = C- empty;
		if(ret < 0){
			ret = 0;
		}
		System.out.println(ret);

		sc.close();
	}
} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		// 整数の入力
		int A = sc.nextInt();
		int B = sc.nextInt();
		int C = sc.nextInt();
		int empty = A - B;
		int ret = C- empty;
		if(ret < 0){
			ret = 0;
		}
		System.out.println(ret);

		sc.close();
	}
}
