import java.util.Arrays;
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();
      int blank = a-b;
      if(blank>c){
        System.out.println(0);
        System.exit(0);
      }
      System.out.println(c-blank);
  }
}
 import java.util.Arrays; Arrays java.util 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();
      int blank = a-b;
      if(blank>c){
        System.out.println(0);
        System.exit(0);
      }
      System.out.println(c-blank);
  }
} 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();
      int blank = a-b;
      if(blank>c){
        System.out.println(0);
        System.exit(0);
      }
      System.out.println(c-blank);
  } main {
    Scanner sc = new Scanner(System.in);
      int a = sc.nextInt();
      int b = sc.nextInt();
      int c = sc.nextInt();
      int blank = a-b;
      if(blank>c){
        System.out.println(0);
        System.exit(0);
      }
      System.out.println(c-blank);
  } 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 int blank = a-b; blank a-b a b if(blank>c){
        System.out.println(0);
        System.exit(0);
      } blank>c blank c {
        System.out.println(0);
        System.exit(0);
      } System.out.println(0) System.out.println System.out System System.out 0 System.exit(0) System.exit System 0 System.out.println(c-blank) System.out.println System.out System System.out c-blank c blank 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();
      int blank = a-b;
      if(blank>c){
        System.out.println(0);
        System.exit(0);
      }
      System.out.println(c-blank);
  }
} 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();
      int blank = a-b;
      if(blank>c){
        System.out.println(0);
        System.exit(0);
      }
      System.out.println(c-blank);
  }
} Main
import java.util.Arrays;
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();
      int blank = a-b;
      if(blank>c){
        System.out.println(0);
        System.exit(0);
      }
      System.out.println(c-blank);
  }
}

