摘要：
A supply chain is a network of retailers（零售商）, distributors（经销商）, and suppliers（供应商）-- everyone involved in moving a product from supplier to customer 阅读全文
摘要：
Given a non-empty tree with root R, and with weight Wi assigned to each tree node Ti. The weight of a path from R to L is defined to be the sum 阅读全文
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Weibo is known as the Chinese version of Twitter. One user on Weibo may have many followers, and may follow many other users as well. Hence a social n 阅读全文
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A gas station has to be built at such a location that the minimum distance between the station and any of the residential housing is as far away as po 阅读全文