原创 58.Length of Last Word (最後一個單詞長度)
描述：Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last
2020-06-28 02:14:29
原创 202.Happy Number
A happy number is a number defined by the following process: Starting with any positive integer, replace the number by
2020-06-28 01:21:08
原创 169.Majority Element （數組中出現次數超過一半的數）
Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2
2020-06-28 01:21:08
原创 203.Remove Linked List Elements（刪除鏈表中值爲X的結點）
題目：Remove all elements from a linked list of integers that have value val. ExampleGiven: 1 --> 2 --> 6 --> 3 --> 4 --
2020-06-28 01:21:08
原创 217.Contains Duplicate(判斷一個數組是否有重複數出現)
題目：Given an array of integers, find if the array contains any duplicates. Your function should return true if any valu
2020-06-28 01:21:08
原创 198.House Robber （求非相鄰正整數的和最大值）
You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed,
2020-06-28 01:21:08
原创 204.Count Primes（1-N中，素數的個數）
題目：Count the number of prime numbers less than a non-negative number, n. 代碼： public class Solution { public int co
2020-06-28 01:21:08
原创 168.Excel Sheet Column Title(28 -> AB)
Given a positive integer, return its corresponding column title as appear in an Excel sheet. For example: 1 -> A
2020-02-24 21:30:48
原创 231.Power of Two(2的N次方)
Given an integer, write a function to determine if it is a power of two. 方法：如果這個數是2的倍數（n%2==0），將這個數除以二（n /=2 ），循環上述操作，最
2020-02-24 21:30:37
原创 226.Invert Binary Tree(交換二叉樹左右結點)
Invert a binary tree. 4 / \ 2 7 / \ / \ 1 3 6 9 to 4 / \ 7 2 / \ / \ 9 6
2020-02-24 21:30:37
原创 225.Implement Stack using Queues (用隊列實現棧)
題目： Implement the following operations of a stack using queues. push(x) -- Push element x onto stack.pop() -- Removes
2020-02-24 21:30:37
原创 206.Reverse Linked List（單鏈表逆置）
Reverse a singly linked list. /** * Definition for singly-linked list. * public class ListNode { * int val; * L
2020-02-24 21:30:37
原创 232.Implement Queue using Stacks(用棧實現隊列)
題目：Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue.pop() --
2020-02-24 21:30:37
原创 171.Excel Sheet Column Number （AB=28）
Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1
2020-02-24 21:30:37
原创 連續子數組的最大和
public Integer findGreatestSum(int[] arr){ if(arr.length ==0) return null;
2018-08-31 18:05:10
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