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();
        
        if (c - (a - b) < 0) {
            System.out.print(0);
            return;
        }
        System.out.print(c - (a - b));
    }

} 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();
        
        if (c - (a - b) < 0) {
            System.out.print(0);
            return;
        }
        System.out.print(c - (a - b));
    }

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

} 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();
        
        if (c - (a - b) < 0) {
            System.out.print(0);
            return;
        }
        System.out.print(c - (a - b));
    }

} 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();
        
        if (c - (a - b) < 0) {
            System.out.print(0);
            return;
        }
        System.out.print(c - (a - b));
    }

}