随笔分类 - leetcode
学习他人or自己完成
摘要：题意： 给定非排序数组，找出其排序后相邻元素的最大差值。 线性时间空间、元素数少于2时返回0、元素值非负且int范围内。 思路： 排序最快nlogn不符合要求； 参考网上，学习了桶排序的方法； 桶排序：按值分段处理； 设定桶大小和桶个数； 因为ans>=(MAX-MIN)/(len-1)； 桶大小：
阅读全文
摘要：You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you nee
阅读全文
摘要：There are n bulbs that are initially off. You first turn on all the bulbs. Then, you turn off every second bulb. On the third round, you toggle every
阅读全文
摘要：Given a string array words, find the maximum value of length(word[i]) * length(word[j]) where the two words do not share common letters. You may assum
阅读全文
摘要：For a undirected graph with tree characteristics, we can choose any node as the root. The result graph is then a rooted tree. Among all possible roote
阅读全文
摘要：121. Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitte
阅读全文
摘要：Given a 2D matrix matrix, find the sum of the elements inside the rectangle defined by its upper left corner (row1, col1) and lower right corner (row2
阅读全文
摘要：Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, ...) which sum to n. For example, given n = 12,
阅读全文
摘要：Write a program to find the n-th ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 1, 2, 3, 4, 5,
阅读全文
摘要：Given an array of numbers nums, in which exactly two elements appear only once and all the other elements appear exactly twice. Find the two elements
阅读全文
摘要：Given a string of numbers and operators, return all possible results from computing all the different possible ways to group numbers and operators. Th
阅读全文
摘要：Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. According to the definition of LCA on Wikipedia: “The lowes
阅读全文
摘要：题意：给出分子和分母，用字符串表示结果，循环的部分用“（）”括起来。 思路： 模拟笔算， 最初根据1/99的情况，设想用path记录余数相同时的间隔步长，但只能用于处理（00..0n）的情况，其中n为[1,9]； 后来采取网上看到用map记录<余数，出现位置>的想法。 通过判断map中key是否重复
阅读全文
摘要：Given a singly linked list L: L0→L1→…→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→… You must do this in-place without altering the nodes' values. For
阅读全文
摘要：Given a linked list, return the node where the cycle begins. If there is no cycle, return null. Note: Do not modify the linked list. note: 开始时，两指针都指向h
阅读全文
摘要：Given a binary tree, determine if it is a valid binary search tree (BST).Assume a BST is defined as follows:The left subtree of a node contains only n...
阅读全文
摘要：Given a binary tree, return theinordertraversal of its nodes' values.For example:Given binary tree{1,#,2,3}, 1 \ 2 / 3return[1,3,2].Note...
阅读全文
摘要：Reverse a linked list from positionmton. Do it in-place and in one-pass.For example:Given1->2->3->4->5->NULL,m= 2 andn= 4,return1->4->3->2->5->NULL.No...
阅读全文
摘要：Given a string containing only digits, restore it by returning all possible valid IP address combinations.For example:Given"25525511135",return["255.2...
阅读全文
摘要：A message containing letters fromA-Zis being encoded to numbers using the following mapping:'A' -> 1'B' -> 2...'Z' -> 26Given an encoded message conta...
阅读全文
浙公网安备 33010602011771号