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();
   if(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B);
 }
} 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();
   if(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B);
 }
} 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(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B);
 } main {
   Scanner sc = new Scanner(System.in);
   int A = sc.nextInt();
   int B = sc.nextInt();
   int C = sc.nextInt();
   if(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B);
 } 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(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B); A-B>=C A-B A B C System.out.println(0) System.out.println System.out System System.out 0 System.out.println(C-A+B) System.out.println System.out System System.out C-A+B C-A C A B 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(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B);
 }
} 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(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B);
 }
} 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();
   if(A-B>=C) System.out.println(0);
   else System.out.println(C-A+B);
 }
}