import java.util.*;

public class Main {

  public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    int a = input.nextInt();
    int b = input.nextInt();
    int c = input.nextInt();

    int remain = a - b;

    int result = c - remain > 0 ? c - remain : 0;


    System.out.println(result);

  }



}

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

  public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    int a = input.nextInt();
    int b = input.nextInt();
    int c = input.nextInt();

    int remain = a - b;

    int result = c - remain > 0 ? c - remain : 0;


    System.out.println(result);

  }



} Main public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    int a = input.nextInt();
    int b = input.nextInt();
    int c = input.nextInt();

    int remain = a - b;

    int result = c - remain > 0 ? c - remain : 0;


    System.out.println(result);

  } main {
    Scanner input = new Scanner(System.in);
    int a = input.nextInt();
    int b = input.nextInt();
    int c = input.nextInt();

    int remain = a - b;

    int result = c - remain > 0 ? c - remain : 0;


    System.out.println(result);

  } Scanner input = new Scanner(System.in); input new Scanner(System.in) int a = input.nextInt(); a input.nextInt() input.nextInt input int b = input.nextInt(); b input.nextInt() input.nextInt input int c = input.nextInt(); c input.nextInt() input.nextInt input int remain = a - b; remain a - b a b int result = c - remain > 0 ? c - remain : 0; result c - remain > 0 ? c - remain : 0 c - remain > 0 c - remain c remain 0 c - remain c remain 0 System.out.println(result) System.out.println System.out System System.out result String[] args args public class Main {

  public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    int a = input.nextInt();
    int b = input.nextInt();
    int c = input.nextInt();

    int remain = a - b;

    int result = c - remain > 0 ? c - remain : 0;


    System.out.println(result);

  }



} public class Main {

  public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    int a = input.nextInt();
    int b = input.nextInt();
    int c = input.nextInt();

    int remain = a - b;

    int result = c - remain > 0 ? c - remain : 0;


    System.out.println(result);

  }



} Main
import java.util.*;

public class Main {

  public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    int a = input.nextInt();
    int b = input.nextInt();
    int c = input.nextInt();

    int remain = a - b;

    int result = c - remain > 0 ? c - remain : 0;


    System.out.println(result);

  }



}


