随笔分类 -  leetcode-algorithms

摘要:Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at 阅读全文
posted @ 2017-09-09 08:25 白常福 阅读(206) 评论(0) 推荐(0)
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 阅读全文
posted @ 2017-09-07 07:34 白常福 阅读(193) 评论(0) 推荐(0)
摘要:Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. For example: Given num = 38, the process is like: 阅读全文
posted @ 2017-09-06 07:24 白常福 阅读(115) 评论(0) 推荐(0)
摘要:Calculate the sum of two integers a and b, but you are not allowed to use the operator + and -. Example:Given a = 1 and b = 2, return 3. 分析:不通过四则运算符号完 阅读全文
posted @ 2017-09-06 07:02 白常福 阅读(126) 评论(0) 推荐(0)
摘要:Given an array of integers where 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements of [1, n] 阅读全文
posted @ 2017-09-05 07:33 白常福 阅读(139) 评论(0) 推荐(0)
摘要:Invert a binary tree. to Trivia:This problem was inspired by this original tweet by Max Howell: 分析:翻转二叉树 思路1: 使用递归的方式,时间复杂度为o(n),空间复杂度为o(n) JAVA CODE 阅读全文
posted @ 2017-09-05 07:02 白常福 阅读(259) 评论(0) 推荐(0)
摘要:Given a word, you need to judge whether the usage of capitals in it is right or not. We define the usage of capitals in a word to be right when one of 阅读全文
posted @ 2017-09-03 07:58 白常福 阅读(160) 评论(0) 推荐(0)
摘要:Given a binary tree, find its maximum depth. The maximum depth is the number of nodes along the longest path from the root node down to the farthest l 阅读全文
posted @ 2017-09-03 07:43 白常福 阅读(124) 评论(0) 推荐(0)
摘要:Given a binary array, find the maximum number of consecutive 1s in this array. Example 1: Input: [1,1,0,1,1,1] Output: 3 Explanation: The first two di 阅读全文
posted @ 2017-09-03 07:29 白常福 阅读(170) 评论(0) 推荐(0)
摘要:Given an array of integers, every element appears twice except for one. Find that single one. Note:Your algorithm should have a linear runtime complex 阅读全文
posted @ 2017-09-03 07:14 白常福 阅读(160) 评论(0) 推荐(0)
摘要:You are playing the following Nim Game with your friend: There is a heap of stones on the table, each time one of you take turns to remove 1 to 3 ston 阅读全文
posted @ 2017-09-03 06:41 白常福 阅读(150) 评论(0) 推荐(0)
摘要:Given a group of two strings, you need to find the longest uncommon subsequence of this group of two strings. The longest uncommon subsequence is defi 阅读全文
posted @ 2017-09-03 06:29 白常福 阅读(143) 评论(0) 推荐(0)
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: Note: 思路:首先要使用层次遍历,因为每次遍历后要计算对应 阅读全文
posted @ 2017-09-01 07:47 白常福 阅读(168) 评论(0) 推荐(0)
摘要:You are given two arrays (without duplicates) nums1 and nums2 where nums1’s elements are subset of nums2. Find all the next greater numbers for nums1' 阅读全文
posted @ 2017-08-31 09:12 白常福 阅读(114) 评论(0) 推荐(0)
摘要:You are given a map in form of a two-dimensional integer grid where 1 represents land and 0 represents water. Grid cells are connected horizontally/ve 阅读全文
posted @ 2017-08-31 07:56 白常福 阅读(125) 评论(0) 推荐(0)
摘要:Write a program that outputs the string representation of numbers from 1 to n. But for multiples of three it should output “Fizz” instead of the numbe 阅读全文
posted @ 2017-08-31 07:31 白常福 阅读(401) 评论(0) 推荐(0)
摘要:In MATLAB, there is a very useful function called 'reshape', which can reshape a matrix into a new one with different size but keep its original data. 阅读全文
posted @ 2017-08-31 07:19 白常福 阅读(216) 评论(0) 推荐(0)
摘要:Given an integer array with even length, where different numbers in this array represent different kinds of candies. Each number means one candy of th 阅读全文
posted @ 2017-08-30 08:18 白常福 阅读(159) 评论(0) 推荐(0)
摘要:Write a function that takes a string as input and returns the string reversed. Example:Given s = "hello", return "olleh" 思路:直接转StringBuffer后reserve即可; 阅读全文
posted @ 2017-08-30 07:37 白常福 阅读(184) 评论(0) 推荐(0)
摘要:Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order. E 阅读全文
posted @ 2017-08-30 07:23 白常福 阅读(99) 评论(0) 推荐(0)