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https://leetcode.com/problems/minimum-index-sum-of-two-lists/ Suppose Andy and Doris want to choose a restaurant for dinner, and they both have a list 阅读全文
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https://leetcode.com/problems/top-k-frequent-words/ Given a non-empty list of words, return the k most frequent elements. Your answer should be sorted 阅读全文
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https://leetcode.com/problems/kth-smallest-element-in-a-sorted-matrix/ Given a n x n matrix where each of the rows and columns are sorted in ascending 阅读全文
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https://leetcode.com/problems/first-unique-character-in-a-string/ Given a string, find the first non-repeating character in it and return it's index. 阅读全文
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https://leetcode.com/problems/sort-characters-by-frequency/ Given a string, sort it in decreasing order based on the frequency of characters. Example 阅读全文
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https://leetcode.com/problems/sort-list/ Sort a linked list in O(n log n) time using constant space complexity. Example 1: Example 2: 代码： 归并排序 学到了 FHF 阅读全文
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https://pintia.cn/problem-sets/994805342720868352/problems/994805345078067200 Suppose that all the keys in a binary tree are distinct positive integer 阅读全文
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https://pintia.cn/problem-sets/994805342720868352/problems/994805344222429184 After each PAT, the PAT Center will announce the ranking of institutions 阅读全文
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https://pintia.cn/problem-sets/994805342720868352/problems/994805343979159552 A clique is a subset of vertices of an undirected graph such that every 阅读全文
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https://pintia.cn/problem-sets/994805342720868352/problems/994805343043829760 This is a problem given in the Graduate Entrance Exam in 2018: Which of 阅读全文
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https://pintia.cn/problem-sets/994805342720868352/problems/994805343727501312 The lowest common ancestor (LCA) of two nodes U and V in a tree is the d 阅读全文