Leetcode: Spiral Matrix II

Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order.

For example,
Given n = 3,

You should return the following matrix:

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

Understand the problem:
The problem gives an integer n, generate a square matrix filled in spiral order. 
For example, n = 0, return empty matrix.
For n = 1, return [1]
For n = 2, return [ [1, 2]
                             [4, 3]
                           ]
For n = 3, return the matrix as shown in the problem. 

So the solution would be the very closed to the Spiral matrix I.


Solution:

?

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public class Solution {     public int[][] generateMatrix(int n) {         int[][] result = new int[n][n];         if (n == 0) {             return result;         }                   int start = 1;         int row = 0;         int col = 0;                   while (n > 0) {             if (n == 1) {                 result[row][col] = start;                 break;             }                           // Move right             for (int i = 0; i < n - 1; i++) {                 result[row][col++] = start++;             }                           // Move down             for (int i = 0; i < n - 1; i++) {                 result[row++][col] = start++;             }                           // Move left             for (int i = 0; i < n - 1; i++) {                 result[row][col--] = start++;             }                           // Move up             for (int i = 0; i < n - 1; i++) {                 result[row--][col] = start++;             }                           row++;             col++;             n -= 2;         }                   return result;     } }