#include <stdio.h>

void main(void){
	long long int n = 0 ;
    scanf("%lld",&n);
    long long int zCount = 0;
    for(int i = 1 ; i <= n ; i++){
        if(i%3 != 0 && i%5 != 0){
            continue;
        }

        if(i%15 == 0){
            zCount += 4;
        }else if(i%3 == 0 && i%5 == 0){
            zCount += 2;
        }
        
    }
    printf("%lld",zCount);
}