public class Main {

    public static void main(String[] args) {
        int price = new java.util.Scanner(System.in).nextInt();
        int pay = 0;
        while (pay < price) {
            pay += 1000;
        }
        System.out.println(pay - price);
    }
}

/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