随笔分类 - Leetcode
leetcode practice notes
摘要:Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n). For example,S = "ADOBECOD
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摘要:Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST. Calling next() will return the n
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摘要:In this problem, a tree is an undirected graph that is connected and has no cycles. The given input is a graph that started as a tree with N nodes (wi
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摘要:Given a Binary Search Tree and a target number, return true if there exist two elements in the BST such that their sum is equal to the given target. E
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摘要:Given two binary trees and imagine that when you put one of them to cover the other, some nodes of the two trees are overlapped while the others are n
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摘要:Given a binary tree, return the tilt of the whole tree. The tilt of a tree node is defined as the absolute difference between the sum of all left subt
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摘要:Given two non-empty binary trees s and t, check whether tree t has exactly the same structure and node values with a subtree of s. A subtree of s is a
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摘要:You are given a binary tree in which each node contains an integer value. Find the number of paths that sum to a given value. The path does not need t
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摘要:Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example:Given the below binary tree and sum
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摘要:112. Path Sum Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals th
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摘要:Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array. Example 1: # it actually examines the know
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摘要:Given a binary search tree (BST) with duplicates, find all the mode(s) (the most frequently occurred element) in the given BST. Assume a BST is define
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摘要:You need to construct a string consists of parenthesis and integers from a binary tree with the preorder traversing way. The null node needs to be rep
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摘要:Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000. Example 1:Input: "bbbab
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摘要:In LeetCode Store, there are some kinds of items to sell. Each item has a price. However, there are some special offers, and a special offer consists
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摘要:In the "100 game," two players take turns adding, to a running total, any integer from 1..10. The player who first causes the running total to reach o
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摘要:Consider the string s to be the infinite wraparound string of "abcdefghijklmnopqrstuvwxyz", so s will look like this: "...zabcdefghijklmnopqrstuvwxyza
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摘要:Given an integer n, generate all structurally unique BST's (binary search trees) that store values 1...n. For example,Given n = 3, your program should
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摘要:Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST'
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摘要:In the computer world, use restricted resource you have to generate maximum benefit is what we always want to pursue. For now, suppose you are a domin
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