quicksort2.rb

#!/usr/bin/ruby
def quicksort(ar)
    return ar if ar.length < 2
    
    left = []
    equal = []
    right = []
    p = ar[0]

    ar.each do |i|
        left.push(i) if i < p
        equal.push(i) if i == p
        right.push(i) if i > p
    end
    
    sub = quicksort(left) + equal + quicksort(right)
    for x in sub
        printf("%d ", x)
    end
    printf("\n")
    return sub
end
           
cnt = gets.chomp.to_i
ar = STDIN.gets.chomp.split(" ").map{|x|x.to_i};
quicksort(ar)