import java.util.Scanner;
class Main{
    public static void main(String args[]){
        Scanner scan = new Scanner(System.in);
        long num = scan.nextInt();
        long sum = 0;
        for(int i =1; i <= num; i++){
            if(i % 3 == 0 && i % 5 == 0){
                //System.out.println("FizzBuzz");
            }else if(i % 3 == 0){
                //System.out.println("Fizz");
            }else if(i % 5 == 0){
                //System.out.println("Buzz");
            }else{
                //System.out.println(i);
                sum = sum + i;
            }
        }
        System.out.println(sum);
    }
}
/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