# 1236. Web Crawler

###### tags: `leetcode`,`bucket`,`medium`

>ref: https://leetcode.com/problems/web-crawler/
>




>1. tc O(n) n for all url
>2. sc O(n) for queue

/**
 * // This is the HtmlParser's API interface.
 * // You should not implement it, or speculate about its implementation
 * interface HtmlParser {
 *     public List<String> getUrls(String url) {}
 * }
 */

class Solution {
    public List<String> crawl(String startUrl, HtmlParser htmlParser) {

        String ori= startUrl.split("/")[2];
        Queue<String> q= new LinkedList<>();
        q.offer(startUrl);
        Set<String> visit= new HashSet<>();
        visit.add(startUrl);

        while(!q.isEmpty()){
            String cur= q.poll();

            for(String str:htmlParser.getUrls(cur)){
                if(!visit.contains(str) && ori.equals(str.split("/")[2])){
                    q.offer(str);
                    visit.add(str);
                }
            }
        }



    return new ArrayList<>(visit);


        
    }
}