[LeetCode] 947. Most Nodes Removed

Zachary 发布于2019-08-16 13:54 / 569人阅读

Problem

On a 2D plane, we place stones at some integer coordinate points. Each coordinate point may have at most one stone.

Now, a move consists of removing a stone that shares a column or row with another stone on the grid.

What is the largest possible number of moves we can make?

Example 1:

Input: stones = [[0,0],[0,1],[1,0],[1,2],[2,1],[2,2]]
Output: 5
Example 2:

Input: stones = [[0,0],[0,2],[1,1],[2,0],[2,2]]
Output: 3
Example 3:

Input: stones = [[0,0]]
Output: 0

Note:

1 <= stones.length <= 1000
0 <= stonesi < 10000

Solution

class Solution {
    public int removeStones(int[][] stones) {
        int m = stones.length;
        int[] parents = new int[m];
        for (int i = 0; i < m; i++) {
            parents[i] = i;
        }
        int count = 0;
        for (int i = 0; i < m; i++) {
            for (int j = i+1; j < m; j++) {
                if (stones[j][0] == stones[i][0] || stones[j][1] == stones[i][1]) {
                    int p1 = find(parents, i);
                    int p2 = find(parents, j);
                    parents[p1] = p2;
                    if (p1 != p2) {
                        count++;
                    }
                }
            }
        }
        return count;
    }
    private int find(int[] parents, int i) {
        if (parents[i] == i) return i;
        else return find(parents, parents[i]);
    }
}

云服务器 GPU云服务器 Most Nodes removed LeetCode

文章版权归作者所有，未经允许请勿转载,若此文章存在违规行为，您可以联系管理员删除。

转载请注明本文地址：https://www.ucloud.cn/yun/72531.html

[LeetCode] 545. Boundary of Binary Tree

Problem Given a binary tree, return the values of its boundary in anti-clockwise direction starting from root. Boundary includes left boundary, leaves, and right boundary in order without duplicate no...

newtrek 2019-08-16 14:26 评论0 收藏0
LeetCode 545. Boundary of Binary Tree 二叉树边界

摘要：二叉树边界题意高频题，必须熟练掌握。逆时针打印二叉树边界。解题思路根据观察，我们发现当为左边界时，也是左边界当为左边界时，为空，则也可以左边界。先加入左边，加入，然后得到两个子树加入，最后加入右边界。 LeetCode 545. Boundary of Binary Tree 二叉树边界Given a binary tree, return the values of its boun...

Astrian 2019-08-16 13:31 评论0 收藏0
[LeetCode] 429. N-ary Tree Level Order Traversal (

429. N-ary Tree Level Order Traversal Given an n-ary tree, return the level order traversal of its nodes values. (ie, from left to right, level by level). For example, given a 3-ary tree:showImg(https...

LiangJ 2019-08-19 11:18 评论0 收藏0
[LeetCode] 684. Redundant Connection

Problem In this problem, a tree is an undirected graph that is connected and has no cycles. The given input is a graph that started as a tree with N nodes (with distinct values 1, 2, ..., N), with one...

lncwwn 2019-08-16 13:55 评论0 收藏0