java code review interview questions

"015-3 Sum (three number and)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title Given an array s of n integers, are there elements a, B, c into s such that A + B + c = 0? Find all unique triplets in the array which gives the sum of zero.Note:Elements in a triplet (A,B,C) must being in the non-descending order. (ie, a≤b≤c)The solution set must not cont

"225-implement stack using queues (stack operations with queues)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" code Download "Https://github.com/Wang-Jun-Chao" Original title Implement the following operations of a stack using queues. Push (x) –push element x onto stack. The Pop () –removes the element on top of t

Java interview is often asked for the 8 large sorting algorithm (analysis + program) Classification: 1 Insert Sort (direct insert sort, hill Sort)2 Exchange sort (bubble sort, quick sort)3 Select sort (Direct select sort, heap sort)4) Merge sort5) Allocation sort (cardinal sort)Maximum required secondary space: merge sortMinimum required auxiliary space: heap SortAverage Speed fastest: quick sort Instabili

"061-rotate list (rotating single linked list)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title Given a list, rotate the "right" by K places, where K is non-negative.For example:Given 1->2->3->4->5->null and k = 2,Return 4->5->1->2->3->null.The main effect of the topic Rotate one single linked table to the right, rotate K position, K non-negative.ide

"105-construct Binary tree from preorder and inorder traversal (constructed two-forked trees by sequence and sequence traversal)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title Given Preorder and inorder traversal of a, construct the binary tree. 　　Note:You could assume that duplicates does not exist into the tree.The main effect of the topic A bina

Give a string, replace more than two _ to one, such as "Hello__world____are__you_ok?", should be treated as "Hello_world_are_you_ok?", the sample code is as follows: Using regular expressions, a word-out version:public static void Main (string args[]) {string str= "Hello__world____are__you_ok?";System.out.println (Str.replaceall ("[_]+", "_")); } Output: Hello_world_are_you_ok?The more troublesome version:public static string replace (String str)

"018-4sum (four-digit and)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title Given an array s of n integers, are there elements a, B, C, and D in s such that A + B + c + d = target? Find all unique quadruplets in the array which gives the sum of target. 　　Note:Elements in a quadruplet (a,b,c,d) must being in the non-descending order. (ie, a≤b≤c≤d)The

"134-gas Station (gas station problem) " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title There are N gas stations along a circular route, where the amount of gas in station I is gas[i].You are have a car with the unlimited gas tank and it costs cost[i] of the gas to the travel from station I to its next station (I+1). You begin the journey with a empty

"226-invert Binary tree (inverted two)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" code Download "Https://github.com/Wang-Jun-Chao" Original title Invert a binary tree. 4 / \ 2 7 /\ /\ 1 3 6 9 To 4 / \ 7 2 /\ /\ 9 6 3 1 The main effect of the topic Flip a binary tree.

"064-minimum path Sum (min path and)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of All numbers along its path. 　　Note: You can only move either down or right at the any.The main effect of the topic Given a square of M x N, the

Java programming example code based on three algorithm questions of quick sorting, java example Overview Quick sorting is an update of the Bubble sorting we have learned before. They all belong to the exchange sorting class and are sorted by continuous comparison and movement. Quick sorting is a very efficient sorting

"046-permutations (order)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title Given A collection of numbers, return all possible permutations.For example,[1,2,3] have the following permutations:[1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], and [3,2,1].The main effect of the topic Given an array, returns all of his permutations.ideas for solving problems

"009-palindrome number (palindrome)" " leetcode-interview algorithm classic-java Implementation" "All topic Directory Index" Original title Determine whether an integer is a palindrome. Do this without extra spaces.The main effect of the topic To determine whether a number is a return word, do not use additional space.ideas for solving problems In order not to use additional space and refer to other reso

saved value" +Newtry_catch_finally_test (). Test ()); } Static intTest () {intx = 1; Try { return++x; }Catch(Exception e) {e.printstacktrace (); return++x; }finally { ++x; System.out.println ("Finally executes first, return finally executes" +x); return++x; } }}Some say that return executes 2 times and finally executes in the middle, which can be understood and may also be convenient roteBut I think that return is executed after finally, after finally execution retur

Computer questions (Elementary)-mouse control small ball instance code (Java) In this section, you can move the ball following the mouse. The Code is as follows: Import java. awt. color; import java. awt. frame; import

Computer questions (Elementary)-Example code of the keyboard control ball (Java) The following code monitors the keyboard and listens to the top, bottom, and left buttons to move the ball up and down: Import java. awt. color; import jav