import java.util.Scanner;
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 m;

    if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    }
  }
} import java.util.Scanner; Scanner 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 m;

    if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    }
  }
} 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 m;

    if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    }
  } main {

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

    if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    }
  } 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 m; m if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    } b>=1 && b<=a && a<=20 && 1<=c && c<=20 1<=c a<=20 b>=1 && b<=a && a<=20 && 1<=c && c<=20 b>=1 b 1 b<=a b a a<=20 a 20 1<=c 1 c c<=20 c 20 {
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    } m = c-(a-b) m c-(a-b) c (a-b) a b if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      } m>=0 m 0 {
        System.out.println(m);
      } System.out.println(m) System.out.println System.out System System.out m {
        System.out.println(0);
      } System.out.println(0) System.out.println System.out System System.out 0 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 m;

    if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    }
  }
} 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 m;

    if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    }
  }
} Main
import java.util.Scanner;
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 m;

    if(b>=1 && b<=a && a<=20 && 1<=c && c<=20){
      m = c-(a-b);
      if(m>=0){
        System.out.println(m);
      }else{
        System.out.println(0);
      }
    }
  }
}
