力扣59.螺旋矩阵

 题目链接59. 螺旋矩阵 II - 力扣（LeetCode）

思路源自力扣一高赞大佬

改为 n*m 型矩阵也一样适用

class Solution {
public:
	vector<vector<int>> generateMatrix(int n) {
		vector<vector<int>>v(n, vector<int>(n, 0));
		int k = 1;
		int left = 0, top = 0;
		int right = n - 1, bottom = n - 1;
		while (k <= n * n) {
			for (int i = left; i <= right; i++) {
				v[top][i] = k++;
			}
			top++;//缩小上边界
			for (int i = top; i <= bottom; i++) {
				v[i][right] = k++;
			}
			right--;//缩小右边界
			for (int i = right; i >= left; i--) {
				v[bottom][i] = k++;
			}
			bottom--;//缩小下边界
			for (int i = bottom; i >= top; i--) {
				v[i][left] = k++;
			}
			left++;//缩小左边界
		}
		return v;
	}
};

初学者，见解不足，如有错误请指出