[LeetCode]Spiral Matrix II

public class Solution {
    public int[][] generateMatrix(int n) {
        int level = (n + 1) / 2;
        int[][] result = new int[n][n];
        int tmp = 1;
        for (int i = 0; i < level; i++) {
            for (int j = i; j < n - i; j++) {
                result[i][j] = tmp++;
            }
            for (int j = i + 1; j < n - i; j++) {
                result[j][n - 1 - i] = tmp++;
            }
            for (int j = n - 2 - i; j >= i; j--) {
                result[n - 1 - i][j] = tmp++;
            }
            for (int j = n - 2 - i; j >= i + 1; j--) {
                result[j][i] = tmp++;
            }
        }
        return result;
    }
}