import java.util.Scanner;
public class Main {
		public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		long a =0;
        for(int i=0; i<=N; i++){
           if(i%3==0 && i%5==0){
           }else if(i%3==0 && i%5!=0){
           }else if(i%3!=0 && i%5==0){
           }else if(i%3!=0 || i%5!=0){
           a +=i;		 
           }
        }
          System.out.println(a);
	}
}
/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