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Lesson

37.1Do Not Use For Loop

We have an array and we need to print the double of each item in this array.

We can do this in so many ways.

First let's see how we do this with the for loop. There are two different ways that we can use:

ruby
numbers = [1,4,8,9,41]
for i in 0...numbers.size do
puts numbers[i]*2
end
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We can also use the for loop a bit differently as shown below:

ruby
numbers = [1,4,8,9,41]
for number in numbers do
puts number*2
end
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Using each is the best way

In JavaScript and some other programming languages, for loops are used a lot. However, in Ruby the most preferred way of iterating through items in an array is by using each.

ruby
numbers = [1,4,8,9,41]
numbers.each do |number|
puts number*2
end
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You can see that this is a simpler approach to achieving the same result.