import java.util.Scanner;

public class Main {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.close();

        N = Math.abs(N-10000);
        System.out.println(N%1000);
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.close();

        N = Math.abs(N-10000);
        System.out.println(N%1000);
    }
} Main public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.close();

        N = Math.abs(N-10000);
        System.out.println(N%1000);
    } main {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.close();

        N = Math.abs(N-10000);
        System.out.println(N%1000);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = sc.nextInt(); N sc.nextInt() sc.nextInt sc sc.close() sc.close sc N = Math.abs(N-10000) N Math.abs(N-10000) Math.abs Math N-10000 N 10000 System.out.println(N%1000) System.out.println System.out System System.out N%1000 N 1000 String args[] args public class Main {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.close();

        N = Math.abs(N-10000);
        System.out.println(N%1000);
    }
} public class Main {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.close();

        N = Math.abs(N-10000);
        System.out.println(N%1000);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.close();

        N = Math.abs(N-10000);
        System.out.println(N%1000);
    }
}
