Write better code: Day 5 - Chronal Calibration

def chronal_calib_part1
  sum = 0

  File.open('advent_of_code/day1.txt', 'r') do |f|
    f.each_line do |line|
      sum += line.to_i
    end
  end  
  sum
end

def chronal_calib_part2
  sum = 0
  frequency = {}
  found_frequency = false
  while found_frequency == false
    File.open('advent_of_code/day1.txt', 'r') do |f|
      f.each_line do |line|
        sum += line.to_i
        if frequency[sum] == true
          frequency[sum] = false
          found_frequency = true 
          break
        else
          frequency[sum] = true 
        end
      end
    end 
  end 
  puts frequency.key(false)
end