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();

    sc.close();

    int a = A - B;

    int ans = 0;

    if (0 < C-a){
      ans = C - a;
    }

    System.out.println(ans);
    
  }

} 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();

    sc.close();

    int a = A - B;

    int ans = 0;

    if (0 < C-a){
      ans = C - a;
    }

    System.out.println(ans);
    
  }

} 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();

    sc.close();

    int a = A - B;

    int ans = 0;

    if (0 < C-a){
      ans = C - a;
    }

    System.out.println(ans);
    
  } main {

    Scanner sc = new Scanner(System.in);
    
    int A = sc.nextInt();
    int B = sc.nextInt();
    int C = sc.nextInt();

    sc.close();

    int a = A - B;

    int ans = 0;

    if (0 < C-a){
      ans = C - a;
    }

    System.out.println(ans);
    
  } 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 sc.close() sc.close sc int a = A - B; a A - B A B int ans = 0; ans 0 if (0 < C-a){
      ans = C - a;
    } 0 < C-a 0 C-a C a {
      ans = C - a;
    } ans = C - a ans C - a C a System.out.println(ans) System.out.println System.out System System.out ans 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();

    sc.close();

    int a = A - B;

    int ans = 0;

    if (0 < C-a){
      ans = C - a;
    }

    System.out.println(ans);
    
  }

} 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();

    sc.close();

    int a = A - B;

    int ans = 0;

    if (0 < C-a){
      ans = C - a;
    }

    System.out.println(ans);
    
  }

} 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();

    sc.close();

    int a = A - B;

    int ans = 0;

    if (0 < C-a){
      ans = C - a;
    }

    System.out.println(ans);
    
  }

}