백준 1964

백준 1964

#include<iostream>

int main()
{
	int n;
	std::cin >> n;
	long long a, b, c;
	

	// 5 10 15 20
	for (int i = 0; i < n; i++)
	{
		if (i == 0)
		{
			a = 0;
			c = 0;
		}
		else
			c = 1 + (2 * i);
		b = 5 * (i+1);

		a = b + a-c

	}
	std::cout << a%45678;
	   
}