54.螺旋矩阵

给你一个 m 行 n 列的矩阵 matrix ，请按照 顺时针螺旋顺序 ，返回矩阵中的所有元素。

思路：

  • 遍历顶部top++
  • 遍历右部right--
  • 遍历底部down--
  • 遍历左部left++
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package com.wereash.scut_hot100.matrix;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

/**
 * @Author: WereAsh
 * @Date:2026-02-03 20:44
 **/
public class Solution054 {
    public static void main(String[] args){
        Scanner scanner=new Scanner(System.in);
        int m=scanner.nextInt();    //矩阵行数
        int n=scanner.nextInt();    //矩阵列数
        scanner.nextLine();
        int[][] matrix=new int[m][n];
        for (int i = 0; i < m; i++) {
            String[] str=scanner.nextLine().split(",");
            for (int j = 0; j < n; j++) {
                matrix[i][j]=Integer.parseInt(str[j]);
            }
        }
        for (int i = 0; i < m; i++) {
            for (int j = 0; j < n; j++) {
                System.out.print(matrix[i][j]);
                if(j<n){
                    System.out.printf(",");
                }
            }
            System.out.println();
        }
        int top=0,down=m-1;
        int left=0,right=n-1;
        List<Integer> list=new ArrayList<>();
        while(true){
            for (int j=left;j<=right;j++){
                list.add(matrix[top][j]);
            }
            if(++top>down) break;
            for (int i=top;i<=down;i++){
                list.add(matrix[i][right]);
            }
            if(--right<left) break;
            for (int j=right;j>=left;j--){
                list.add(matrix[down][j]);
            }
            if(--down<top) break;
            for (int i=down;i>=top;i--){
                list.add(matrix[i][left]);
            }
            if(++left>right) break;
        }
        for (int i:list){
            System.out.printf(i+",");
        }
    }

}