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How to write negative loop in ruby like for(i=index; i >= 0; i --)

How can I write a loop in Ruby that counts down, similar to the following C-style for loop?

for (i = 25; i >= 0; i--) { 
    print i;
}
question from:https://stackoverflow.com/questions/8926477/how-to-write-negative-loop-in-ruby-like-fori-index-i-0-i

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by (71.8m points)

There are many ways to perform a decrementing loop in Ruby:

First way:

for i in (10).downto(0)
  puts i
end

Second way:

(10).downto(0) do |i|
  puts i
end

Third way:

i=10;
until i<0
  puts i
  i-=1
end

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