#ProjectEuler/Python/Problem4.py
#Matthew Ellison
# Created: 01-28-19
#Modified: 03-28-19
#Find the largest palindrome made from the product of two 3-digit numbers
#Unless otherwise listed, all of my non-standard imports can be gotten from my pyClasses repository at https://bitbucket.org/Mattrixwv/pyClasses
"""
	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/>.
"""


from Stopwatch import Stopwatch

__lowestNum = 100
__highestNum = 1000


def Problem4():
	#Setup the variables
	palindromes = []		#Holds all of the palindromes
	currentNum = 0			#Holds the product of the two numbers I am currently working on

	#Loop through every number from __lowestNum to __highestNum twice and multiply every number together
	for num1 in range(__lowestNum, __highestNum + 1):
		for num2 in range(num1, __highestNum + 1):	#You can start at num1 because 100 * 101 == 101 * 100
			currentNum = num1 * num2
			#If the number is a palindrome add it to the list of palindromes, otherwise ignore it
			#Using strings makes it easier to determine a palindrome
			if(str(currentNum) == str(currentNum)[::-1]):
				palindromes.append(currentNum)

	#Sort the palindromes so that the last element is the largest
	palindromes.sort()

	#Print the results
	print("The largest palindrome made from the product of two 3-digit numbers is " + str(palindromes[len(palindromes) - 1]))

#If you are running this file, automatically start the correct function
if __name__ == '__main__':
	timer = Stopwatch()	#Determines the algorithm's run time
	timer.start()	#Start the timer
	Problem4()		#Call the function that answers the question
	timer.stop()	#Stop the timer
	#Print the results of the timer
	print("It took " + timer.getString() + " to run this algorithm")

"""Results:
The largest palindrome made from the product of two 3-digit numbers is 906609
It took 177.314 milliseconds to run this algorithm
"""