随笔分类 - LeetCode
摘要：Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST.Callingnext()will return the next...
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摘要：Given a positive integer, return its corresponding column title as appear in an Excel sheet. For example: Example 1: Example 2: Example 3: Credits:Spe
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摘要：Related to question Excel Sheet Column TitleGiven a column title as appear in an Excel sheet, return its corresponding column number.For example: A...
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摘要：Given a list of non negative integers, arrange them such that they form the largest number. Example 1: Example 2: Note: The result may be very large,
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摘要：Given an integer n, return the number of trailing zeroes in n!. Example 1: Example 2: Note: Your solution should be in logarithmic time complexity. Cr
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摘要：A peak element is an element that is strictly greater than its neighbors. Given an integer array nums, find a peak element, and return its index. If t
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摘要：Given a binary tree, return the preorder traversal of its nodes' values. Example: Input: [1,null,2,3] 1 \ 2 / 3 Output: [1,2,3] Follow up: Recursive s
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摘要：Given a linked list, return the node where the cycle begins. If there is no cycle, return null. To represent a cycle in the given linked list, we use
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摘要：Given a linked list, determine if it has a cycle in it. To represent a cycle in the given linked list, we use an integer pos which represents the posi
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摘要：Given a non-empty array of integers, every element appears twice except for one. Find that single one. Note: Your algorithm should have a linear runti
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摘要：Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each inp
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摘要：You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order, and each of their nodes conta
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摘要：Given the heads of two singly linked-lists headA and headB, return the node at which the two lists intersect. If the two linked lists have no intersec
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摘要：The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font
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摘要：Given a signed 32-bit integer x, return x with its digits reversed. If reversing x causes the value to go outside the signed 32-bit integer range [-2^
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摘要：Implement the myAtoi(string s) function, which converts a string to a 32-bit signed integer (similar to C/C++'s atoi function). The algorithm for myAt
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摘要：Given an integer x, return true if x is a palindrome, and false otherwise. Example 1: Input: x = 121 Output: true Explanation: 121 reads as 121 from l
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摘要：Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol Value I 1 V 5 X 10 L 50 C 100 D 500 M 1000 For example, two
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摘要：Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol Value I 1 V 5 X 10 L 50 C 100 D 500 M 1000 For example, two
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摘要：Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) -- Push element x onto stack. pop() -- Remov
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