Problem:
Score : 400 points

Problem Statement

Let {\rm comb}(n,r) be the number of ways to choose r objects from among n objects, disregarding order.
From n non-negative integers a_1, a_2, ..., a_n, select two numbers a_i > a_j so that {\rm comb}(a_i,a_j) is maximized.
If there are multiple pairs that maximize the value, any of them is accepted.

Constraints

2 \leq n \leq 10^5

0 \leq a_i \leq 10^9

a_1,a_2,...,a_n are pairwise distinct.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

n
a_1 a_2 ... a_n

Output

Print a_i and a_j that you selected, with a space in between.

Sample Input 1

5
6 9 4 2 11

Sample Output 1

11 6

\rm{comb}(a_i,a_j) for each possible selection is as follows:

\rm{comb}(4,2)=6

\rm{comb}(6,2)=15

\rm{comb}(6,4)=15

\rm{comb}(9,2)=36

\rm{comb}(9,4)=126

\rm{comb}(9,6)=84

\rm{comb}(11,2)=55

\rm{comb}(11,4)=330

\rm{comb}(11,6)=462

\rm{comb}(11,9)=55

Thus, we should print 11 and 6.

Sample Input 2

2
100 0

Sample Output 2

100 0

Solution in C# (.NET Core 3.1.201) (judge verdict: Runtime Error)

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

namespace ABC
{
    class ProgramD
    {
        static void Main(string[] args)
        {
            var n = long.Parse(Console.ReadLine());
            var list = Console.ReadLine().Split(" ").Select(x => long.Parse(x)).ToList();
            list.Sort();

            var max = 0L;
            var pair = (0L, 0L);

            for (var i = 0; i < n - 1; i++)
            {
                for (var j = i + 1; j < n; j++)
                {
                    var c = comb(list[j], list[i]);
                    if (max < c)
                    {
                        max = c;
                        pair = (list[j], list[i]);
                    }
                    // Console.WriteLine(string.Join(", ", max, pair.Item1, pair.Item2));
                }
            }

            Console.WriteLine(string.Join(" ", pair.Item1, pair.Item2));
        }

        static long comb(long n, long r)
        {
            if (r==0) return 1;
            var p = fact(n, n - r + 1);
            return p / fact(r);
        }

        static long fact(long s, long e = 0)
        {
            // Console.WriteLine(string.Join(", ", "fact", s, e));
            if (s == e)
            {
                return Math.Max(s, 1);
            }
            return s * fact(s - 1, e);
        }
    }
}