26 lines
692 B
Ruby
26 lines
692 B
Ruby
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#Given an array 'a',create a product array where product[i]==product of all elements except a[i]
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#Time-complexity: O(n), Space-complexity: O(n),Auxiliary-space: O(1)
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def product_array(a)
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len=a.length
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product=Array.new(len,1) # Initilaize product array elements to 1
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temp=1
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#Loop to store product of left elements
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for i in 0...len
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product[i]=temp
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temp*=a[i]
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end
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temp=1 #reset temp variable to 1
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#Loop to multiply stored left products with right products
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for i in (len-1).downto(0)
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product[i]*=temp
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temp*=a[i]
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end
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return product
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end
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product_array([1,2,3,4,5,6]) # => [720, 360, 240, 180, 144, 120]
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