LeetCode 841 题解

https://leetcode.com/problems/keys-and-rooms/description/

题目大意：给你n个房间，每个房间里有一些钥匙，你在房间0，问能不能去到所有的房间。

解题思路：直接搜索一下就好了

class Solution {
    public boolean canVisitAllRooms(List<List<Integer>> rooms) {
        int n = rooms.size();
        int[] a= new int[n];
        a[0] = 1;
        int cnt =1;
        Queue<Integer> qt= new LinkedList<>();
        for(int i=0;i<rooms.get(0).size();i++)
        {
            if( a[rooms.get(0).get(i)] ==0) {
                qt.offer(rooms.get(0).get(i));
                a[rooms.get(0).get(i)] = 1;
                cnt++;
            }
        }
        while(!qt.isEmpty())
        {
            int tmp  = qt.poll();
            for(int i=0;i<rooms.get(tmp).size();i++)
            {
                int m = rooms.get(tmp).get(i);
                if(  a[m] ==0)
                {
                    a[m]=1;
                    cnt++;
                    qt.offer(m);
                }
            }
        }
        if(cnt==n)
            return true;
        return false;
    }
}