#include <stdio.h>
#include <stdlib.h>
//Problem 1: multiples of 3 and 5
int main(){
	int max = 1000;
	int i, sum = 0;
	
	for (i; i<max; i++)
		if (!(i%3) || !(i%5))
			 sum+=i;
	
	printf("%d\n", sum);
}