Spiral Matrix

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:

[ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ]]

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

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对的地方

这道题的考察的是具体实现，抽象思维不是太好还是看了提示。

代码：

  public List<Integer> spiralOrder(int[][] matrix) {        List<Integer> result = new ArrayList<>();        if(matrix.length == 0) return result;                int left = 0, right = matrix[0].length-1;        int top =0, bottom = matrix.length-1;                while(left<=right && top <=bottom){            for(int i=left;i<=right;i++){                result.add(matrix[top][i]);            }            top++;            if(left>right || top > bottom ) break;                        for(int i=top;i<=bottom;i++){                result.add(matrix[i][right]);            }            right--;            if(left>right || top > bottom ) break;                        for(int i=right;i>=left;i--){                result.add(matrix[bottom][i]);            }            bottom--;            if(left>right || top > bottom ) break;                        for(int i=bottom;i>=top;i--){                result.add(matrix[i][left]);            }            left++;            if(left>right || top > bottom ) break;        }                return result;    }