// binary search

#include <iostream>
#include <cstdlib>
using namespace std;

int main()
{
	// ************** declaration statements ***********
	int numbers[] = {2, 4, 5, 11, 13, 20, 34, 39, 50, 52, 59, 64, 66, 70, 75, 76, 81, 83, 85, 92};
	int first = 0;
	int last = 19;
	int mid = 0;
	int key = 0;
	bool found = false;

	cout << "Enter the value you would like to search for: ";
	cin >> key;

	while (first <= last && !found) 
	{
		mid = (first + last) / 2;

		if (key > numbers[mid])
		{
			first = mid + 1;
		}
		else if (key < numbers[mid]) 
		{
			last = mid - 1;
		}
		else
		{
			cout << "The value" << key << " was found in position " << mid << endl;
			found = true;
		}
	}

	if (!found)
	{
		cout << "The value " << key << " was not found" << endl;
	}

	system("pause");
	return 0;
}// end of main


