import java.util.Scanner;

public class Main {
    static int A;
    static int B;
    static int C;

    public static void main(String args[]) {
        Scanner scanner = new Scanner(System.in);
        A = scanner.nextInt();
        B = scanner.nextInt();
        C = scanner.nextInt();

        scanner.close();

        if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        }
    }
} import java.util.Scanner; Scanner java.util public class Main {
    static int A;
    static int B;
    static int C;

    public static void main(String args[]) {
        Scanner scanner = new Scanner(System.in);
        A = scanner.nextInt();
        B = scanner.nextInt();
        C = scanner.nextInt();

        scanner.close();

        if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        }
    }
} Main static int A; A static int B; B static int C; C public static void main(String args[]) {
        Scanner scanner = new Scanner(System.in);
        A = scanner.nextInt();
        B = scanner.nextInt();
        C = scanner.nextInt();

        scanner.close();

        if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        }
    } main {
        Scanner scanner = new Scanner(System.in);
        A = scanner.nextInt();
        B = scanner.nextInt();
        C = scanner.nextInt();

        scanner.close();

        if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        }
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) A = scanner.nextInt() A scanner.nextInt() scanner.nextInt scanner B = scanner.nextInt() B scanner.nextInt() scanner.nextInt scanner C = scanner.nextInt() C scanner.nextInt() scanner.nextInt scanner scanner.close() scanner.close scanner if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        } A - B <= C A - B A B C {
            System.out.println(C - (A - B));
        } System.out.println(C - (A - B)) System.out.println System.out System System.out C - (A - B) C (A - B) A B {
            System.out.println(0);
        } System.out.println(0) System.out.println System.out System System.out 0 String args[] args public class Main {
    static int A;
    static int B;
    static int C;

    public static void main(String args[]) {
        Scanner scanner = new Scanner(System.in);
        A = scanner.nextInt();
        B = scanner.nextInt();
        C = scanner.nextInt();

        scanner.close();

        if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        }
    }
} public class Main {
    static int A;
    static int B;
    static int C;

    public static void main(String args[]) {
        Scanner scanner = new Scanner(System.in);
        A = scanner.nextInt();
        B = scanner.nextInt();
        C = scanner.nextInt();

        scanner.close();

        if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        }
    }
} Main
import java.util.Scanner;

public class Main {
    static int A;
    static int B;
    static int C;

    public static void main(String args[]) {
        Scanner scanner = new Scanner(System.in);
        A = scanner.nextInt();
        B = scanner.nextInt();
        C = scanner.nextInt();

        scanner.close();

        if(A - B <= C) {
            System.out.println(C - (A - B));
        } else {
            System.out.println(0);
        }
    }
}