Given a positive integer n, generate a square matrix filled with elements from 1 to n2 in spiral order.
Example:
Input: 3
Output:
[
[ 1, 2, 3 ],
[ 8, 9, 4 ],
[ 7, 6, 5 ]
]
1 class Solution { 2 public: 3 vector<vector<int>> generateMatrix(int n) { 4 int dir[4][2] = { 0,1,1,0,0,-1,-1,0 }, dire = 0, x = 0, y = 0; 5 vector<vector<int>>ans(n, vector<int>(n, -1)); 6 for (int i = 1; i <= (n * n); i++) { 7 ans[x][y] = i; 8 int nextx = x + dir[dire][0], nexty = y + dir[dire][1]; 9 if (nextx >= n || nextx < 0 || nexty >= n || nexty < 0 || ans[nextx][nexty] != -1) { 10 dire = (dire + 1) % 4; 11 nextx=x+dir[dire][0], nexty = y + dir[dire][1]; 12 } 13 x = nextx, y = nexty; 14 } 15 return ans; 16 } 17 };
19.2.9 [LeetCode 59] Spiral Matrix II
原文：https://www.cnblogs.com/yalphait/p/10357555.html
