Ruby - rmvDuplicates.txt

take an array of integers and return an array with all the unique values in the proper order.


def unique(integers)
    uniArr = []
    for i in integers do
        unless uniArr.include?(i)
        uniArr << i
        end
    end
    uniArr
end

unique([1,1,2,3,5])
 => [1,2,3,5]
unique([7,7,7,7,7,7,7,7,7,7,7,7,7,1])
 => [7,1]




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# Define the unique method that removes duplicates

def unique(integers)
	new=[]
	integers.each {|x| new.push(x) unless new.include?(x) }
	new
end





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# Define the unique method that removes duplicates
def unique(integers)
  integers.to_set.to_a
end





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def unique(integers)
  integers & integers
end

^^^explanation^^^

“&” is ‘set intersection’

“ary & other_ary” 
=> new_ary 

	Set Intersection — Returns a new array containing elements common to the two arrays, excluding any duplicates. The order is preserved from the original array.

It compares elements using their hash and eql? methods for efficiency.