import java.util.Scanner;

public class Main{
    public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int s=0;
    if(n<=1000){
        s=1000-n;
        System.out.println(s);
    }else if(n<=2000){
        s=2000-n;
        System.out.println(s);
    }else if(n<=3000){
        s=3000-n;
        System.out.println(s);
    }else if(n<=4000){
        s=4000-n;
        System.out.println(s);
    }else if(n<=5000){
        s=5000-n;
        System.out.println(s);
    }else if(n<=6000){
        s=6000-n;
        System.out.println(s);
    }else if(n<=7000){
        s=7000-n;
        System.out.println(s);
    }else if(n<=8000){
        s=8000-n;
        System.out.println(s);
    }else if(n<=9000){
        s=9000-n;
        System.out.println(s);
    }else if(n<=10000){
        s=10000-n;
        System.out.println(s);
    }
    
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz