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Fix typo for segment trees #314

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Fix typo for segment trees #314

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2 changes: 1 addition & 1 deletion content/english/hpc/data-structures/segment-trees.md
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Expand Up @@ -453,7 +453,7 @@ To store these segment sums compactly, the Fenwick tree ditches the Eytzinger la
- the element $9$ would hold the sum on the $[8, 9]$ range ($-86$),
- the element $10$ would hold the sum on the $[10, 10]$ range ($-52$, the element itself).

How to compute this range for a given element $k$ (the left boundary, to be more specific: the right boundary is always the element $k$ itself) quicker than simulating the descend down the tree? Turns out, there is a smart bit trick that works when the tree size is a power of two and we use one-based indexing — just remove the least significant bit of the index:
How to compute this range for a given element $k$ (the left boundary, to be more specific: the right boundary is always the element $k$ itself) quicker than simulating the descent down the tree? Turns out, there is a smart bit trick that works when the tree size is a power of two and we use one-based indexing — just remove the least significant bit of the index:

- the left bound for element $7 + 1 = 8 = 1000_2$ is $0000_2 = 0$,
- the left bound for element $9 + 1 = 10 = 1010_2$ is $1000_2 = 8$,
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