2022.07.03 (lc_6111_counts the number of ways to place houses)

  Method ： simulation

 

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {
    public int[][] spiralMatrix(int m, int n, ListNode head) {
        int[][] res = new int[m][n];
        int up = 0, down = m - 1, left = 0, right = n - 1;
        while (true) {
            // From left to right 
            for (int col = left; col <= right; col++) {
                if (head != null) {
                    res[up][col] = head.val;
                    head = head.next;
                } else {
                    res[up][col] = -1;
                }
            }
            if (++up > down) break;
            // From top to bottom 
            for (int row = up; row <= down; row++) {
                if (head != null) {
                    res[row][right] = head.val;
                    head = head.next;
                } else {
                    res[row][right] = -1;
                }
            }
            if (--right < left) break;
            // From right to left 
            for (int col = right; col >= left; col--) {
                if (head != null) {
                    res[down][col] = head.val;
                    head = head.next;
                } else {
                    res[down][col] = -1;
                }
            }
            if (--down < up) break;
            // From bottom to top 
            for (int row = down; row >= up; row--) {
                if (head != null) {
                    res[row][left] = head.val;
                    head = head.next;
                } else {
                    res[row][left] = -1;
                }
            }
            if (++left > right) break;
        }
        return res;
    }
}