백준-설탕 배달.cpp.txt

#include <iostream>
using namespace std;

int main()
{
	int weight;
	int count = 0;
	bool check = true;
	cin >> weight;
	while (check)
	{
		if (weight % 5 == 0)
		{

			int num_5 = (weight / 5);
			for (int i = 0; i < num_5; i++)
				count++;
			check = false;
		}
		else
		{
			int num_5 = (weight / 5);

			int ex_weight = weight;
			ex_weight-=5 * num_5;
			
			if (ex_weight % 3 == 0)
			{

				count++;
				count += num_5;
				check = false;
			}
			else {
				int c = weight - 3;
				if(c>=0)
				{
					weight -= 3;
					count++;
				}
				else {
					cout << "-1" << endl;
					return 0;
				}
			}
		}
	}
	cout << count;

	return 0;
}