
import java.util.*;

public class Main {

    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();


        c -= a -b;
        if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        }

    }

} import java.util.*; util.* java public class Main {

    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();


        c -= a -b;
        if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        }

    }

} Main public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();


        c -= a -b;
        if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        }

    } main {

        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();


        c -= a -b;
        if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        }

    } Scanner in = new Scanner(System.in); in new Scanner(System.in) int a = in.nextInt(); a in.nextInt() in.nextInt in int b = in.nextInt(); b in.nextInt() in.nextInt in int c = in.nextInt(); c in.nextInt() in.nextInt in c -= a -b c a -b a b if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        } c <= 0 c 0 {
            System.out.println(0);
        } System.out.println(0) System.out.println System.out System System.out 0 {
            System.out.println(c);
        } System.out.println(c) System.out.println System.out System System.out c String[] args args public class Main {

    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();


        c -= a -b;
        if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        }

    }

} public class Main {

    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();


        c -= a -b;
        if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        }

    }

} Main

import java.util.*;

public class Main {

    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();


        c -= a -b;
        if (c <= 0) {
            System.out.println(0);
        } else {
            System.out.println(c);
        }

    }

}
