"Leetcode-Interview algorithm classic-java implementation" "054-spiral Matrix (Spiral matrix)"

054-spiral matrix (spiral matrix) "leetcode-Interview algorithm classic-java Implementation" "All topics Directory Index" Original Question

Given a matrix of M x n elements (m rows, n columns), return all elements of the matrix in spiral order.
For example,
Given the following matrix:

123456789 ]]

You should return [1,2,3,6,9,8,7,4,5] .

Main Topic

Given a m*n matrix, enter the spiral order of all the elements.

Thinking of solving problems

Using the computed output method, the first line is processed, the right column is processed, the following line is processed, and the left column is processed until all the elements have been processed.

Code Implementation

Algorithm implementation class

Import Java.util.arraylist;import Java.util.list;public class Solution {public list<integer> Spiralorder (int[][]Matrix) {list<integer> result = new Arraylist<> ( -);if(Matrix= = NULL | |Matrix. length = =0||Matrix[0].length = =0) {returnResult }//Only one row in the case        if(Matrix. length = =1) { for(intIMatrix[0]) {result.add (i); }returnResult }//Only one column of the situation        if(Matrix[0].length = =1) { for(inti =0; I <Matrix. length; i++) {Result.add (MatrixI [0]); }returnResult }//Calculate how many laps        introw =Matrix. length;intCol =Matrix[0].length;intCycle = row < col?        Row:col; Cycle = (cycle +1) /2;intRound =0;//record is currently the first few laps        intleft =0;intright =Matrix[0].length-1;inttop =0;intDown =Matrix. Length-1;intTotal = col*row;intCount =0; while(Round < cycle) {//Top row             for(inti = left; I <= right && count < total;                i++) {count++; Result.add (Matrix[Round]            [i]); } top++;//            //Right column             for(inti = top; I <= && count < total;                i++) {count++; Result.add (MatrixI [Col-round-1]); } right--;//Bottom row             for(inti = right; I >= left && count < total;                i--) {count++; Result.add (Matrix[Row-round-1][i]); } down--;//left column             for(inti = down; I >= top && count < total;                i--) {count++; Result.add (MatrixI            [round]);            } left++;        round++; }returnResult }}

Evaluation Results

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"Leetcode-Interview algorithm classic-java implementation" "054-spiral Matrix (Spiral matrix)"