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

int main()
{
	const string a[] = {
		"Alabama",        // 0
		"Alaska",         // 1
		"Arizona",        // 2
		"Arkansas",       // 3
		"California",     // 4
		"Colorado",       // 5
		"Connecticut",    // 6
		"Delaware",       // 7
		"Florida",        // 8
		"Georgia",        // 9

		"Hawaii",         //10
		"Idaho",          //11
		"Illinois",       //12
		"Indiana",        //13
		"Iowa",           //14
		"Kansas",         //15
		"Kentucky",       //16
		"Louisiana",      //17
		"Maine",          //18
		"Maryland",       //19

		"Massachusetts",  //20
		"Michigan",       //21
		"Minnesota",      //22
		"Mississippi",    //23
		"Missouri",       //24
		"Montana",        //25
		"Nebraska",       //26
		"Nevada",         //27
		"New Hampshire",  //28
		"New Jersey",     //29

		"New Mexico",     //30
		"New York",       //31
		"North Carolina", //32
		"North Dakota",   //33
		"Ohio",           //34
		"Oklahoma",       //35
		"Oregon",         //36
		"Pennsylvania",   //37
		"Rhode Island",   //38
		"South Carolina", //39

		"South Dakota",   //40
		"Tennessee",      //41
		"Texas",          //42
		"Utah",           //43
		"Vermont",        //44
		"Virginia",       //45
		"Washington",     //46
		"West Virginia",  //47
		"Wisconsin",      //48
		"Wyoming"         //49
	};

	const size_t n {size(a)};  //the number of elements in the array

	cout << "Please input the name of a state: ";
	string name;
	getline(cin, name);

	if (!cin) {
		cerr << "Sorry, couldn't input the name.\n";
		return EXIT_FAILURE;
	}

	if (n == 0) {
		cerr << "Sorry, the array is empty.\n";
		return EXIT_FAILURE;
	}

	//If the name is in the array, its subscript is
	//lo <= subscript <= hi
	//That means that if hi < lo, the name is not in the array.
	int lo {0};
	int hi {n};

	while (lo <= hi) {
		const int mid {(lo + hi) / 2};   //the average of lo and hi
		if (a[mid] == name) {
			cout << "Found \"" << name << "\" at subscript "
				<< mid << ".\n";
			return EXIT_SUCCESS;
		} else if (a[mid] < name) {
			lo = mid + 1;  //Our guess was too low.
		} else {
			hi = mid - 1;  //Our guess was too high.
		}
	}

	cout << "Sorry, \"" << name << "\" is not in the array.\n";
	return EXIT_SUCCESS;
}