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# (Mono 4.6.2.0) (judge verdict: Runtime Error)

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

namespace test
{
    class Program
    {
        static void Main(string[] args)
        {
            var N = int.Parse(Console.ReadLine());
            var A = Console.ReadLine().Split(' ').Select(s => int.Parse(s)).OrderByDescending(a=>a).ToArray();
            long big = 0, ansn = 0, ansr = 0;

            for(var i = 1; i < N; i++)
            {
                var comb = Combination(A[0], A[i]);
                if (comb > big)
                {
                    big = comb;
                    ansn = A[0];
                    ansr = A[i];
                }
            }

            Console.WriteLine(ansn + " " + ansr);
        }

        public static long Combination(long n, long r)
        {
            if (n < 0 || r < 0 || r > n) throw new ArgumentException("不正な引数です．");

            if (n - r < r) r = n - r;
            if (r == 0) return 1;
            if (r == 1) return n;

            long[] numerator = new long[r];
            long[] denominator = new long[r];

            for (long k = 0; k < r; k++)
            {
                numerator[k] = n - r + k + 1;
                denominator[k] = k + 1;
            }

            for (long p = 2; p <= r; p++)
            {
                long pivot = denominator[p - 1];
                if (pivot > 1)
                {
                    long offset = (n - r) % p;
                    for (long k = p - 1; k < r; k += p)
                    {
                        numerator[k - offset] /= pivot;
                        denominator[k] /= pivot;
                    }
                }
            }

            long result = 1;

            for (long k = 0; k < r; k++)
            {
                if (numerator[k] > 1) result *= numerator[k];
            }

            return result;
        }
    }
}