Ruby travel time

Question

I'm new to ruby and I'm having a hard time trying to figure out how to calculate a random travel time until it passes 1000 miles. So far, I can't figure out why it doesn't output the results, it just stays with the user input. Help please

def travel_time()
    printf "Pick a vehicle: \n"
    printf "1.  Bicycle \n"
    printf "2.  Car \n"
    printf "3.  Jet Plane \n"
    puts "Choose 1-3: \n"
    vehicle = gets.chomp

  case vehicle
    when "1"
        #Bicycle: 5-15 miles per hour
        time = 0
        distance = 0
        until distance > 1000 do
         speed = Random.rand(5...15)
         distance = speed * 1
         time = time + 1
        end
        puts "The number of hours it took to travel 1000 miles was #{time} hours"
    when "2"
        #Car: 20-70 miles per hour
        time = 0
        distance = 0
        until distance > 1000 do
        speed = Random.rand(20...70)
        distance = speed * 1
        time = time + 1
        end
        puts "The number of hours it took to travel 1000 miles was #{time} hours"

    when "3"
        #Jet Plane: 400-600 miles per hour
        time = 0
        distance = 0
        until distance > 1000 do
        speed = Random.rand(400...600)
        distance = speed * 1
        time = time + 1
        end
        puts "The number of hours it took to travel 1000 miles was #{time} hours"
    end
end
travel_time

Answer 1

You have an infinite loop here:

until distance > 1000 do
  speed = Random.rand(5...15)
  distance = speed * 1
  time = time + 1
end

This loop will never ende because the biggest value distance can get is 15, so i think you want to add to distance, not replace it; son try using += instead of =:

until distance > 1000 do
  speed = Random.rand(5...15)
  distance += speed * 1
  time = time + 1
end

Same goes for all loops in each case.

How can I save the maximum speed and return it in a statement like I have done?

One way to do it would be to add another variable (i.e. max_speed) and assign speed value to it whenever speed is greater than max_speed:

time = 0
distance = 0
max_speed = 0

until distance > 1000 do
  speed = Random.rand(5...15)
  max_speed = speed if speed > max_speed
  distance += speed * 1
  time = time + 1
end

puts "The maximum speed was #{max_speed} miles per hour"

Another way would be to use an array (although i prefer the first option):

speed = []

until distance > 1000 do
  speed << Random.rand(5...15)
  distance += speed.last * 1
  time = time + 1
end

puts "The maximum speed was #{speed.max} miles per hour"