Given an array [1,3,4,2] we should get an array [0,0,0,2]. Can someone suggest a quick method for doing this
Given an array [1,3,4,2] we should get an array [0,0,0,2]. Can someone suggest a quick method for doing this
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This is essentially the inversion problem which can be solved using segment tree or binary indexes tree in O(nlogn). ( You can search for it online)
Iterate from the left and imagine the array is the skyscrapers with height a[i]. Now we want to maintain all skyscrapers visible from i. To do so just maintain a stack. O(n).
But If I input 1 3 5 4, the output is 2. What am I missing?