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package leetcode;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Comparator;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import java.util.Map.Entry;

import java.util.Scanner;

/**

* Given a non-empty array of integers, return the k most frequent elements.

For example,

Given [1,1,1,2,2,3] ，return 1.

Note:

You may assume k is always valid, 1 ≤ k ≤ number of unique elements.

Your algorithm’s time complexity must be better than O(n log n), where n is the array’s size

* @author Ting

*

*/

public class Main{

public static void main(String[] args) {

List list=new ArrayList();

Scanner sc=new Scanner(System.in);

sc.useDelimiter(",|\n");

while(sc.hasNext()){

System.out.println(sc.nextInt());

//list.add(sc.nextInt());

}

sc.close();

Map map=new HashMap<>();

for(int i:list){

int item=0;

if(map.containsKey(list.get(i))){

item=map.get(i);

item++;

}else{

item=1;

}

map.put(list.get(i), item);

}

MapCompareByValue mcp=new MapCompareByValue();

List> maplist=new ArrayList<>();

Collections.sort(maplist,mcp);

System.out.println(maplist.get(0).getKey());

}

}

class MapCompareByValue implements Comparator>{

@Override

public int compare(Entry o1, Entry o2) {

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

}

}