Problem:
Score: 300 points

Problem Statement

We have N voting papers. The i-th vote (1 \leq i \leq N) has the string S_i written on it.

Print all strings that are written on the most number of votes, in lexicographical order.

Constraints

1 \leq N \leq 2 \times 10^5

S_i (1 \leq i \leq N) are strings consisting of lowercase English letters.

The length of S_i (1 \leq i \leq N) is between 1 and 10 (inclusive).

Input

Input is given from Standard Input in the following format:

N
S_1
:
S_N

Output

Print all strings in question in lexicographical order.

Sample Input 1

7
beat
vet
beet
bed
vet
bet
beet

Sample Output 1

beet
vet

beet and vet are written on two sheets each, while beat, bed, and bet are written on one vote each. Thus, we should print the strings beet and vet.

Sample Input 2

8
buffalo
buffalo
buffalo
buffalo
buffalo
buffalo
buffalo
buffalo

Sample Output 2

buffalo

Sample Input 3

7
bass
bass
kick
kick
bass
kick
kick

Sample Output 3

kick

Sample Input 4

4
ushi
tapu
nichia
kun

Sample Output 4

kun
nichia
tapu
ushi

Solution in C# (Mono 4.6.2.0) (judge verdict: Time Limit Exceeded)

using System;
using System.Text;
using System.Collections.Generic;
using System.Linq;
using System.Collections;

namespace Equeue
{
    
    
    class Equeue
    {
      static Node[] Nodes;
        static void Main(string[] args)
        {
            var N = long.Parse(Console.ReadLine());
            //var A = Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToArray();
            var dic = new Dictionary<string,long>();
          
            for(int i = 0; i < N ;i++){
              var S = Console.ReadLine();
              if(dic.ContainsKey(S)){
                dic[S]++;
              }else{
                dic.Add(S,1);
              }
            }
            long max =dic.OrderByDescending(val=>val.Value).First().Value;
            var ans = new List<String>();
             
            foreach(KeyValuePair<string, long> item in dic) {
              if(item.Value == max){
                ans.Add(item.Key);
              }
            }
            
            ans.Sort();
          
            for(int i = 0; i < ans.Count ;i++){
              Console.WriteLine(ans[i]);
            }

            
        }
      
      
        static bool WFS(long st){
          var q = new Queue<Node>();
          var tmp = Nodes[st];
          tmp.loc = 100;
          q.Enqueue(tmp);
          
          while(q.Count > 0){
            tmp = q.Dequeue();
            foreach(KeyValuePair<long,long> item in tmp.adj) {
              var child = Nodes[item.Key];
              //Console.WriteLine(item.Key+" "+child.loc+" "+item.Value);
              if(child.loc != -1 && (child.loc != (item.Value+tmp.loc))){
                return false;
              }else if(child.loc == -1){
                child.loc = item.Value+tmp.loc;
                q.Enqueue(Nodes[item.Key]);
                //Console.WriteLine(item.Key+" "+child.loc+" "+item.Value);
              }
              
            }
          }
          return true;
        }      
      
    }
  


    public class Node{
      public long loc = -1;
      public Dictionary<long,long> adj = new Dictionary<long,long>();
    }
  
  
    public class PriorityQueue<T> : IEnumerable<T>
    {
        private readonly List<T> _data = new List<T>();
        private readonly IComparer<T> _comparer;
        private readonly bool _isDescending;

        public PriorityQueue(IComparer<T> comparer, bool isDescending = true)
        {
            _comparer = comparer;
            _isDescending = isDescending;
        }

        public PriorityQueue(Comparison<T> comparison, bool isDescending = true)
            : this(Comparer<T>.Create(comparison), isDescending)
        {
        }

        public PriorityQueue(bool isDescending = true)
            : this(Comparer<T>.Default, isDescending)
        {
        }

        public void Enqueue(T item)
        {
            _data.Add(item);
            var childIndex = _data.Count - 1;
            while (childIndex > 0)
            {
                var parentIndex = (childIndex - 1) / 2;
                if (Compare(_data[childIndex], _data[parentIndex]) >= 0)
                    break;
                Swap(childIndex, parentIndex);
                childIndex = parentIndex;
            }
        }

        public T Dequeue()
        {
            var lastIndex = _data.Count - 1;
            var firstItem = _data[0];
            _data[0] = _data[lastIndex];
            _data.RemoveAt(lastIndex--);
            var parentIndex = 0;
            while (true)
            {
                var childIndex = parentIndex * 2 + 1;
                if (childIndex > lastIndex)
                    break;
                var rightChild = childIndex + 1;
                if (rightChild <= lastIndex && Compare(_data[rightChild], _data[childIndex]) < 0)
                    childIndex = rightChild;
                if (Compare(_data[parentIndex], _data[childIndex]) <= 0)
                    break;
                Swap(parentIndex, childIndex);
                parentIndex = childIndex;
            }
            return firstItem;
        }

        public T Peek()
        {
            return _data[0];
        }

        private void Swap(int a, int b)
        {
            var tmp = _data[a];
            _data[a] = _data[b];
            _data[b] = tmp;
        }

        private int Compare(T a, T b)
        {
            return _isDescending ? _comparer.Compare(b, a) : _comparer.Compare(a, b);
        }

        public int Count => _data.Count;

        public IEnumerator<T> GetEnumerator()
        {
            return _data.GetEnumerator();
        }

        IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
    }
}