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https://leetcode.com/problems/balanced-binary-tree/ Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binar 阅读全文
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https://leetcode.com/problems/sum-of-left-leaves/ Find the sum of all left leaves in a given binary tree. Example: 代码： 阅读全文
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https://pintia.cn/problem-sets/994805342720868352/problems/994805502658068480 To evaluate the performance of our first year CS majored students, we co 阅读全文
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https://vjudge.net/contest/67836#problem/I Given a set of sticks of various lengths, is it possible to join them end-to-end to form a square? Input Th 阅读全文