#include <iostream>
#include<cmath>
#include<ctime>
#include<string>
#include <iomanip>
#include <fstream>

using namespace std;

int main()
{

	int firstprofit = 0;
	int quantity = 0;
	int q3 = 1;

	//the targeted profit >> 50000
	cout << "Enter the profit ";
	int endProfit;
	cin >> endProfit;

	//first five quantity 1 * 1000+2 * 4000
	firstprofit += 9000;
	do
	{
		//the remaining quantity(q3) which is 50000(endProfit) - 9000(firstProfit) / 5
		if (q3 == (endProfit - 9000) / 5)

			firstprofit += q3 * 5;
		else
			q3++;

	} while (firstprofit <= endProfit);

	//the whole quantity
	quantity += 1000 + 4000 + q3;

	cout << quantity;






}