// CS101 Laboratory #3: Inquiring about the IF statement
// Description:  This program provides some demonstrations of the
//      IF statement.

// Program expects as input three numbers in nondecreasing order. It then
// determines whether the numbers correspond to lengths of sides of a triangle

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

int main() {

	int Side1;
	int Side2;
	int Side3;
	// prompt use to type 3 numbers in nondecreasing order

	cout << "\n\n"
	 << "Please type in lengths of sides of your possible triangle.\n"
	 << "We require that the numbers be in nondecreaing order.\n"
	 << "That is, first number <= second number <= third number.\n\n";

	cout << "First number: ";
	cin  >> Side1;

	cout << "Second number: ";
	cin  >> Side2;

	cout << "Third number: ";
	cin  >> Side3;

	cout << endl;

	// make sure user followed our rules

	if ( (Side1 > Side2) || (Side2 > Side3) ) {
		// they did not follow the instructions

		cout << "Bad numbers. Program quits\n";

		return 0;
	}

	// check to see whether numbers do form sides of a triangle or not

	if (Side1 + Side2 <= Side3) {
		// numbers do not form a triangle

		cout << "Numbers are not the sides of a triangle.\n";

	}
	else if (Side1 == Side3) {
		// numbers form a equilateral triangle

		cout << "Numbers are the sides of an equilateral triangle.\n";
	}
	else if ( (Side1 == Side2) || (Side2 == Side3) ) {   
		// numbers form an isosceles triangle

		cout << "Numbers are the sides of an isosceles triangle.\n";
	}
	else { // triangle is scalene
		cout  << "Numbers are the sides of a scalene triangle.\n";
	}

	// we are all done
	return 0;
}