LeetCode59. 螺旋矩阵 II

给定一个正整数 n，生成一个包含 1 到 n2 所有元素，且元素按顺时针顺序螺旋排列的正方形矩阵。

示例:

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

class Solution {
	public int[][] generateMatrix(int n) {
		int[][] result = new int[n][n];
		int len = (n / 2) + (n % 2);
		int value = 0;
		for (int i = 0; i < len; ++i) {
			int c = i, l = i;
			int endc = n - i - 1, endl = n - i - 1;
			if (c == endc && l == endl) {
				result[c][l] = ++value;
				return result;
			}
			while (l != endl) {
				result[c][l++] = ++value;
			}
			while (c != endc) {
				result[c++][l] = ++value;
			}
			while (l != i) {
				result[c][l--] = ++value;
			}
			while (c != i) {
				result[c--][l] = ++value;
			}
		}

		return result;
	}

}