import java.util.*;
import static java.lang.System.*;

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();
		int ans = 0;
		
		ans = c - (a - b);
		if (ans < 0)
			ans = 0;
		out.println(ans);

	}
} import java.util.*; util.* java import static java.lang.System.*; import static java.lang.System.*; import static java.lang.System.*; 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();
		int ans = 0;
		
		ans = c - (a - b);
		if (ans < 0)
			ans = 0;
		out.println(ans);

	}
} 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();
		int ans = 0;
		
		ans = c - (a - b);
		if (ans < 0)
			ans = 0;
		out.println(ans);

	} main {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int ans = 0;
		
		ans = c - (a - b);
		if (ans < 0)
			ans = 0;
		out.println(ans);

	} 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 ans = 0; ans 0 ans = c - (a - b) ans c - (a - b) c (a - b) a b if (ans < 0)
			ans = 0; ans < 0 ans 0 ans = 0 ans 0 out.println(ans) out.println out ans 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();
		int ans = 0;
		
		ans = c - (a - b);
		if (ans < 0)
			ans = 0;
		out.println(ans);

	}
} 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();
		int ans = 0;
		
		ans = c - (a - b);
		if (ans < 0)
			ans = 0;
		out.println(ans);

	}
} Main
import java.util.*;
import static java.lang.System.*;

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();
		int ans = 0;
		
		ans = c - (a - b);
		if (ans < 0)
			ans = 0;
		out.println(ans);

	}
}