import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
		Scanner scan = new Scanner(System.in);
      	int a = scan.nextInt();
      	int b = scan.nextInt();
      	int c = scan.nextInt();      
      
      	int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ;
        System.out.println(d);
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws Exception {
		Scanner scan = new Scanner(System.in);
      	int a = scan.nextInt();
      	int b = scan.nextInt();
      	int c = scan.nextInt();      
      
      	int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ;
        System.out.println(d);
    }
} Main public static void main(String[] args) throws Exception {
		Scanner scan = new Scanner(System.in);
      	int a = scan.nextInt();
      	int b = scan.nextInt();
      	int c = scan.nextInt();      
      
      	int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ;
        System.out.println(d);
    } main {
		Scanner scan = new Scanner(System.in);
      	int a = scan.nextInt();
      	int b = scan.nextInt();
      	int c = scan.nextInt();      
      
      	int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ;
        System.out.println(d);
    } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) int a = scan.nextInt(); a scan.nextInt() scan.nextInt scan int b = scan.nextInt(); b scan.nextInt() scan.nextInt scan int c = scan.nextInt(); c scan.nextInt() scan.nextInt scan int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ; d ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ( a - b ) - c < 0 ( a - b ) - c ( a - b ) a b c 0 Math.abs(( a - b ) - c) Math.abs Math ( a - b ) - c ( a - b ) a b c 0 System.out.println(d) System.out.println System.out System System.out d String[] args args public class Main {
    public static void main(String[] args) throws Exception {
		Scanner scan = new Scanner(System.in);
      	int a = scan.nextInt();
      	int b = scan.nextInt();
      	int c = scan.nextInt();      
      
      	int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ;
        System.out.println(d);
    }
} public class Main {
    public static void main(String[] args) throws Exception {
		Scanner scan = new Scanner(System.in);
      	int a = scan.nextInt();
      	int b = scan.nextInt();
      	int c = scan.nextInt();      
      
      	int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ;
        System.out.println(d);
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
		Scanner scan = new Scanner(System.in);
      	int a = scan.nextInt();
      	int b = scan.nextInt();
      	int c = scan.nextInt();      
      
      	int d = ( a - b ) - c < 0 ? Math.abs(( a - b ) - c) : 0 ;
        System.out.println(d);
    }
}
