import java.util.*;

public class TopNPopularPathServiceImpl{

private static String[][] useData = null;

public void setup(String[][] data) {

this.useData = data;

}

public String[] getTopNPopularPathes(int n) {

if (useData == null) return new String[0];

List<String> urlList = new ArrayList<>();

Set<String> urlSet = new HashSet<>();

Map<String,Integer> urlMap = new TreeMap<>();

for (int i=0;i < useData.length;i++){

String url = "";

if (useData[i].length <= 3) {

for (int k = 0; k < useData[i].length; k++)

url += useData[i][k];

urlList.add(url);//将拼接好的url放入list数组中

urlSet.add(url);//将拼接好的url放入lset数组中，去重

} else {

int j = 0,length = 3;

while (length <= useData[i].length) {

for (int k = j; k < j + 3; k++)//第一位循环3位，第二位循环3位......

url += useData[i][k];

urlList.add(url);

urlSet.add(url);

j++;length++;url="";

}

}

}

int num = 0,urlSetSize = 0;

List<String> urlSetToList = new ArrayList<>(urlSet);

while (urlSetSize < urlSetToList.size()) {

for (String urlStr : urlList)

if ((urlSetToList.get(urlSetSize)).equals(urlStr)) num++;

urlMap.put(urlSetToList.get(urlSetSize),num);//将set里的元素和list里的元素比较，得出个数

urlSetSize++;num = 0;

}

String [] result = new String[n];

Comparator<Map.Entry<String,Integer>> valueComparator = new Comparator<Map.Entry<String, Integer>>() {//排序比较器

@Override

public int compare(Map.Entry<String, Integer> o1, Map.Entry<String, Integer> o2) {

return o2.getValue()-o1.getValue();

//o2.getValue()-o1.getValue();数组按value降序排列

//o1.getValue()-o2.getValue();数组按value升序排列

}

};

List<Map.Entry<String,Integer>> valueList = new ArrayList<>(urlMap.entrySet());//map转list排序

Collections.sort(valueList,valueComparator);//排序

int stringLength = 0;

while (stringLength < n){

result[stringLength] = valueList.get(stringLength).getKey();

stringLength++;

}

return result;

}

}

class Data {

public static void main(String[] args) {

TopNPopularPathServiceImpl pathService = new TopNPopularPathServiceImpl();

String[][] data = {{"/", "subscribers", "filter", "export"}, {"/", "subscribers", "filter", "export"}, {"/", "catalog", "edit"}};

pathService.setup(data);

Utils utils = new Utils();

System.out.println(utils.strArray(pathService.getTopNPopularPathes(3)));

}

}