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();
      if(b+c > a) System.out.println(b+c-a);
      else System.out.println(0);
    }
} 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();
      if(b+c > a) System.out.println(b+c-a);
      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();
      if(b+c > a) System.out.println(b+c-a);
      else System.out.println(0);
    } main {
    	Scanner sc = new Scanner(System.in);
      int a = sc.nextInt();
      int b = sc.nextInt();
      int c = sc.nextInt();
      if(b+c > a) System.out.println(b+c-a);
      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 if(b+c > a) System.out.println(b+c-a);
      else System.out.println(0); b+c > a b+c b c a System.out.println(b+c-a) System.out.println System.out System System.out b+c-a b+c b c a 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();
      if(b+c > a) System.out.println(b+c-a);
      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();
      if(b+c > a) System.out.println(b+c-a);
      else System.out.println(0);
    }
} 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();
      if(b+c > a) System.out.println(b+c-a);
      else System.out.println(0);
    }
}