一、题目

二、代码 

按上右下左的行添加到链表

class Solution {public List<Integer> spiralOrder(int[][] matrix) {List<Integer> result = new LinkedList<>();if(matrix.length == 0){return result;}//初始化int left = 0;int top = 0;int right = matrix[0].length - 1;int bottom = matrix.length - 1;int total =  matrix[0].length * matrix.length;while(total > 0){//最上一行for(int i = left; i <= right && total > 0; i++){result.add(matrix[top][i]);total--;}top++;//最右一行,此时的top已经改变了for(int i = top; i <= bottom && total > 0; i++){result.add(matrix[i][right]);total--;}right--;//最下一行for(int i = right; i >= left && total > 0; i--){result.add(matrix[bottom][i]);total--;}bottom--;//最左一行for(int i = bottom; i >= top && total > 0; i--){result.add(matrix[i][left]);total--;}left++;}return result;}
}