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Question about segment trees
By idek_bro, history, 2 years ago, In English

Does a segment tree provide any functionality other than storing the sums of sub arrays? Is the usage of unordered_sets to store the sums of subarrays from [0,0] to [0,n], to calculate the sum of the subarray [l,r] as [0,r]-[0,l-1] a valid alternative to segment trees?

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2 years ago, # |
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Segment Trees also allow you to update values in $$$O(logN)$$$ time. Using Prefix Sums would not allow you to update values in $$$O(logN)$$$ time, because in the worst case, you'd need to change all $$$O(N)$$$ prefix sums (which happens when the first element in the array is changed).

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2 years ago, # |
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There is no such easy thing like prefix sums that can be used for finding minimum on segment. And the segment tree is one of the most easy and effective ways to do this. It also allows you to do tons of crazy stuff. For example, adding Fibonacci sequence on segment and then calculating sum on segment.

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2 years ago, # |
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Segment tree can store monoids

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2 years ago, # |
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Why are you learning segment trees after you do 2 codeforces problems

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