Segment tree segment update hdu 1698 Just a Hook, segment update hdu

Segment tree segment update hdu 1698 Just a Hook, segment update hdu

N metal rods, and q are given. At the beginning, each metal rod has a value of 1. Each operation can replace the metal rod from x to y. The copper is 1 and the silver is 2, the value of gold is 3, and the total value of all metal rods is calculated.

Lazy tags are used to update segments of a line segment. lazy tags are used to update an interval without updating the end, update only to the first interval that meets the update range (that is, the maximum interval in the range), and add the lazy mark to the node. When you need to update it to the subnode of the node, the lazy tag is transferred to the subnode, which greatly improves the efficiency.

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