realcj2018-优快云博客

原创 669. Trim a Binary Search Tree

Given a binary search tree and the lowest and highest boundaries as L and R, trim the tree so that all its elements lies in [L, R] (R >= L). You might need to change the root of the tree, so the re...

2018-09-13 20:40:02 190

原创 500. Keyboard Row

Given a List of words, return the words that can be typed using letters of alphabet on only one row’s of American keyboard like the image below. Example 1: 题解：def find_words(words): r...

2018-08-31 11:55:12 181

原创 617. Merge Two Binary Trees

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 not. You need to merge them into a new binary tre...

2018-08-30 21:42:44 209

原创 476. Number Complement

Given a positive integer, output its complement number. The complement strategy is to flip the bits of its binary representation. Note:The given integer is guaranteed to fit within the range of a ...

2018-08-30 21:22:36 194

原创 13. Roman to Integer

Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. For example, two is written as II in Roman numeral, just two one’s added together. Twelve is written as, XII, whic...

2018-08-27 10:02:51 163

原创 237. Delete Node in a Linked List

Write a function to delete a node (except the tail) in a singly linked list, given only access to that node. Given linked list – head = [4,5,1,9], which looks like following: Example 1: Example...

2018-08-26 17:26:45 139

原创 566. Reshape the Matrix

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. You’re given a matrix represented by a two-dime...

2018-08-26 16:51:37 154

原创 412. Fizz Buzz

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 number and for the multiples of five output “Buzz”. Fo...

2018-08-26 16:12:25 176

原创 118. Pascal's Triangle

Given a non-negative integer numRows, generate the first numRows of Pascal’s triangle. 题解：package com.leetcode;import java.util.*;public class PascalTriangle { public static void mai...

2018-08-26 15:55:06 158

原创 806. Number of Lines To Write String

We are to write the letters of a given string S, from left to right into lines. Each line has maximum width 100 units, and if writing a letter would cause the width of the line to exceed 100 units, it...

2018-08-25 13:18:58 198

原创 463. Island Perimeter

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/vertically (not diagonally). The grid is completely ...

2018-08-25 12:46:23 186

原创 589. N-ary Tree Preorder Traversal

Given an n-ary tree, return the preorder traversal of its nodes’ values.For example, given a 3-ary tree: Return its preorder traversal as: [1,3,5,6,2,4].package com.leetcode;import java.u...

2018-08-24 20:05:44 214

原创 693. Binary Number with Alternating Bits

Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values. Example 1: Example 2: Example 3: Example 4: 题解：packa...

2018-08-24 19:47:22 229

原创 590. N-ary Tree Postorder Traversal

Given an n-ary tree, return the postorder traversal of its nodes’ values.For example, given a 3-ary tree: Return its postorder traversal as: [5,6,3,2,4,1].题解：package com.leetcode;import...

2018-08-24 14:06:59 297

原创 108. Convert Sorted Array to Binary Search Tree

Given an array where elements are sorted in ascending order, convert it to a height balanced BST. For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the...

2018-08-24 13:30:31 167

原创 258. Add Digits

Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. Example: Input: 38 Output: 2 Explanation: The process is like: 3 + 8 = 11, 1 + 1 = 2. ...

2018-08-23 22:20:57 228

原创 559. N叉树的最大深度

给定一个N叉树，找到其最大深度。最大深度是指从根节点到最远叶子节点的最长路径上的节点总数。例如，给定一个 3叉树 : 我们应返回其最大深度，3。说明: 树的深度不会超过 1000。树的节点总不会超过 5000。题解：#include <iostream>#include <vector>using std::cout;usin...

2018-08-23 21:47:48 200

原创 811. 子域名访问计数

一个网站域名，如”discuss.leetcode.com”，包含了多个子域名。作为顶级域名，常用的有”com”，下一级则有”leetcode.com”，最低的一级为”discuss.leetcode.com”。当我们访问域名”discuss.leetcode.com”时，也同时访问了其父域名”leetcode.com”以及顶级域名 “com”。给定一个带访问次数和域名的组合，要求分别计算每个...

2018-08-23 21:13:25 227

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