import java.util.Scanner;

public class Main {
    public static void main(String args[]) {
        new Main().run();
    }

    private void run() {
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();

        int ans = (A - B) - C;
        if(ans < 0) ans = Math.abs(ans);
        else ans = 0;

        System.out.println(ans);
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String args[]) {
        new Main().run();
    }

    private void run() {
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();

        int ans = (A - B) - C;
        if(ans < 0) ans = Math.abs(ans);
        else ans = 0;

        System.out.println(ans);
    }
} Main public static void main(String args[]) {
        new Main().run();
    } main {
        new Main().run();
    } new Main().run() new Main().run new Main() String args[] args private void run() {
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();

        int ans = (A - B) - C;
        if(ans < 0) ans = Math.abs(ans);
        else ans = 0;

        System.out.println(ans);
    } run {
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();

        int ans = (A - B) - C;
        if(ans < 0) ans = Math.abs(ans);
        else ans = 0;

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

    private void run() {
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();

        int ans = (A - B) - C;
        if(ans < 0) ans = Math.abs(ans);
        else ans = 0;

        System.out.println(ans);
    }
} public class Main {
    public static void main(String args[]) {
        new Main().run();
    }

    private void run() {
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();

        int ans = (A - B) - C;
        if(ans < 0) ans = Math.abs(ans);
        else ans = 0;

        System.out.println(ans);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String args[]) {
        new Main().run();
    }

    private void run() {
        Scanner scanner = new Scanner(System.in);
        int A = scanner.nextInt();
        int B = scanner.nextInt();
        int C = scanner.nextInt();

        int ans = (A - B) - C;
        if(ans < 0) ans = Math.abs(ans);
        else ans = 0;

        System.out.println(ans);
    }
}
