22 lines
549 B
Ruby
22 lines
549 B
Ruby
#Given an array replace every element with the next greatest element(largest number on right side) on the right side of the array,
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#as there is no element on the right side of last element replace it with -1
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#Time-complexity: O(n),Auxiliary-space:O(1)
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def replace_with_nge(a)
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len=a.length
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max=a[len-1]
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a[len-1]=-1
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for i in (len-2).downto(0)
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current=a[i]
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a[i]=max
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if current>max
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max=current
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end
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end
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return a
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end
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replace_with_nge([5,8,12,10,4,6]) # => [12, 12, 10, 6, 6, -1]
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