Leetcode 54: 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].

 

Note: this soluntion beats 100% C# submissions.

 1 public class Solution {
 2     public IList<int> SpiralOrder(int[,] matrix) {
 3         int rows = matrix.GetLength(0), cols = matrix.GetLength(1);
 4         var result = new List<int>();
 5         
 6         int upRow = 0, downRow = rows - 1, leftCol = 0, rightCol = cols - 1;
 7         while (upRow <= downRow && leftCol <= rightCol)
 8         {
 9             if (upRow == downRow)
10             {
11                 for (int j = leftCol; j <= rightCol; j++)
12                 {
13                     result.Add(matrix[upRow, j]);
14                 }
15                 break;
16             }
17             
18             if (leftCol == rightCol)
19             {
20                 for (int j = upRow; j <= downRow; j++)
21                 {
22                     result.Add(matrix[j, rightCol]);
23                 }
24                 break;
25             }
26             
27             for (int j = leftCol; j <= rightCol; j++)
28             {
29                 result.Add(matrix[upRow, j]);
30             }
31             
32             for (int j = upRow + 1; j <= downRow - 1; j++)
33             {
34                 result.Add(matrix[j, rightCol]);
35             }
36                         
37             for (int j = rightCol; j >= leftCol; j--)
38             {
39                 result.Add(matrix[downRow, j]);
40             }
41             
42             for (int j = downRow - 1; j > upRow; j--)
43             {
44                 result.Add(matrix[j, leftCol]);
45             }
46             
47             leftCol++;
48             rightCol--;
49             upRow++;
50             downRow--;
51         }
52         
53         return result;
54     }
55 }

 

转载于:https://www.cnblogs.com/liangmou/p/7807562.html