#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include <functional>
#include <iomanip>
using namespace std;

#define rep(p,q) for(int i = p;i < q;i++)

#define LL long long int

#define inf 10000000000

//15
int main(void) {
	LL n;
	cin >> n;
	int count = 0;
	count += n / 25;
	n %= 25;
	count += n / 10;
	n %= 10;
	count += n / 5;
	n %= 5;
	count += n;
	cout << count << endl;
}
