# 2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.
      # What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?

      # Brute force: can check by 20 then downward from 20 for divisible / This takes a long time
      # Trick: the next multiplier is always a multiple of the prior multiplier

      require "benchmark"

      def smallestDivisibleValue(num)                # num is the amount of results to generate
        resultArray = [1]                            # the first value is a given and preset
        index = 0                                    # index of the first array element
        multiplier = 1                               # initialize the multiplier, used to determine the currentTestValue until value is found
        count = 2                                    # identifies the current position to be evaluated (starts off checking for the 2nd value)
        found = false                                # used to check whether a correct value is found

        while (true)
          currentTestValue = resultArray[index] * multiplier  # currentTestValue is a multiple of the prior result
          (1..count).to_a.reverse.each do |i|
            if(currentTestValue % i === 0)           # currentTestValue must be evenly divisible by all 'i' values to be 'found'
              found = true
            else
              found = false                     
              break                                  # exit the loop in the event that the currentTestValue is not divisble
            end
          end

          multiplier += 1                            # increment the multiplier by 1

          if found === true
            resultArray.push(currentTestValue)
            multiplier = 1                           # reset the multiplier back to 1, needs to happen after multiplier increment (prevent pre-increment)
            index += 1                               # increment the index
            count += 1                          
          end 

          return resultArray if resultArray.length === num   # saves the result into an array and returns the array when length is equal to user input number
        end	
      end

      time = Benchmark.realtime do
        puts smallestDivisibleValue(20)[19]          # the 19th index value is the 20th element in the area, thus the answer
      end

      puts "Time elasped #{time*1000} milliseconds"

      # output:
      # 232792560
      # Time elasped 0.316 milliseconds