/**********************************************************************
	Ed Yakabosky	CSE 103		Section 003
	This is the third lab program for CSE 103.
	This program is designed to take parameters as two integers x
		and y such that x is nonzero and returns x^y.
	input: integers x and y.
	output: 
**********************************************************************/

#include <iostream>

using namespace std;

double power(int x, int y); // Function prototype.

int main()
{
	// Initializes variables.
	int x = 0;
	int y = 0;

	cout << "Please enter a value for x: ";
	cin >> x;
	cout << endl;
	while (x <= 0) // If x not more than 0, this error statement outputs.
	{
		cout << "Please re-enter x.  It must be greater than 0.";
		cin >> x;
		cout << endl;
	}
	cout << "Please enter a value for y: ";
	cin >> y;
	cout << endl;

	cout << "x^y is roughly: " << power(x, y) << "!!!!!!!!" << endl;

	return 0;
}

/* This function computes a base, x, to an exponent, y.  Its parameters are
   input integer values for x and y; the statement is not a void statement
   so we do not need them to be reference parameters.  The function returns
   a double x^y. */
double power(int x, int y)
{
	if (y == 0) // Returns 1 if y is 0.
	{
		return 1;
	}
	if (y == 1) // Returns x if y is 0.
	{
		return x;
	}
	if (y > 1) // Returns x and recurses the power function if y is greater than 1.
	{
		return x * power(x, y - 1);
	}

	else
	{ // Returns 1 divided by a negative y.  This will be a decimal, so function returns
	  //	 a double.
		return (1/power(x, -y));
	}
}