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John got a full mark on PAT. He was so happy that he decided to hold a raffle（抽奖） for his followers on Weibo -- that is, he would select winners from 阅读全文
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Given some segments of rope, you are supposed to chain them into one rope. Each time you may only fold two segments into loops and chain them into one 阅读全文
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In graph theory, an Eulerian path is a path in a graph which visits every edge exactly once. Similarly, an Eulerian circuit is an Eulerian path which 阅读全文
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Suppose that all the keys in a binary tree are distinct positive integers. A unique binary tree can be determined by a given pair of postorder and ino 阅读全文