//numberHunt.cxx
//By Sp 07 CS1300 Class
//6 February 2007
//Program guesses a number that the user is thinking of

#include<iostream>
#include<cstdlib>
using namespace std;

int main()
{
	int low, high, mid;
	char ans;
	bool flag;

	cout << "Think of a number between 0 and 1,000,000..." << endl;

	//Prime the loop
	low = 0;
	high = 1000000;
	flag = false;
	while(!flag) 
	{
		//Invariant: low <= your number <= high
		mid = (low + high)/2;
		cout << "Is your number equal to " << mid << " (y/n)? ";
		cin >> ans;
		if(ans == 'y' || ans == 'Y')
		{
			flag = true;
		}
		else
		{
			cout << "Is your number less than " << mid << " (y/n)? ";
			cin >> ans;
			if(ans == 'y' || ans == 'Y')
			{
				high = mid - 1;
			}
			else
			{
				low = mid + 1;
			}
		}
		//Invariant: low <= your number <= high
	}

	cout << "Your number is "<< mid << endl;
	cout << "I knew that all along!" << endl;

	return EXIT_SUCCESS;
	
}