//ProjectEuler/Java/Problem12.java
//Matthew Ellison
// Created: 03-04-19
//Modified: 03-28-19
//What is the value of the first triangle number to have over five hundred divisors?
//Unless otherwise listed all non-standard includes are my own creation and available from https://bibucket.org/Mattrixwv/JavaClasses
/*
	Copyright (C) 2019  Matthew Ellison

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Lesser General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public License
	along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/


import mattrixwv.Stopwatch;
import mattrixwv.Algorithms;

import java.util.ArrayList;


public class Problem12{
	private static final Long GOAL_DIVISORS = 500L;	//The minimum number of divisors that you want
	public static void main(String[] argv){
		Stopwatch timer = new Stopwatch();	//Allows timing of the algorithm

		//Setup the other variables
		Boolean foundNumber = false;	//TO flag whether the number has been found
		Long sum = 1L;
		Long counter = 2L;	//The next number to be added to the sum to make a triangular number
		ArrayList<Long> divisors = new ArrayList<Long>();

		//Start the timer
		timer.start();

		//Loop until you find the appropriate number
		while((!foundNumber) && (sum > 0)){
			divisors = Algorithms.getDivisors(sum);
			//If the number of divisors is correct set the flag
			if(divisors.size() > GOAL_DIVISORS.intValue()){
				foundNumber = true;
			}
			//Otherwise add to the sum and increase the next number
			else{
				sum += counter;
				++counter;
			}
		}

		//Stop the timer
		timer.stop();

		//Print the results
		System.out.printf("The triangulare number %d is the sum of all numbers >= %d and has %d divisors\n", sum, counter - 1, divisors.size());
		System.out.println("It took " + timer.getStr() + " to run this algorithms");
	}
}

/* Results:
The triangulare number 76576500 is the sum of all numbers >= 12375 and has 576 divisors
It took 758.987 milliseconds to run this algorithms
*/