팩토리얼 0의 개수

#include <algorithm>
#include <iostream>
#include <stdio.h>
#include <vector>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <string>
#include <cmath>
#include <time.h>
using namespace std;


int main() {
	//freopen("input.txt", "rt", stdin);

	int num;

	scanf("%d", &num);

	
	printf("%d", (num/5)+(num/25)+(num/125));
	


	return 0;
}