Problem:
Score : 400 points

Problem Statement

We have N integers. The i-th integer is A_i.

Find \sum_{i=1}^{N-1}\sum_{j=i+1}^{N} (A_i \mbox{ XOR } A_j), modulo (10^9+7).

What is \mbox{ XOR }?

The XOR of integers A and B, A \mbox{ XOR } B, is defined as follows:

When A \mbox{ XOR } B is written in base two, the digit in the 2^k's place (k \geq 0) is 1 if either A or B, but not both, has 1 in the 2^k's place, and 0 otherwise.

For example, 3 \mbox{ XOR } 5 = 6. (In base two: 011 \mbox{ XOR } 101 = 110.)

Constraints

2 \leq N \leq 3 \times 10^5

0 \leq A_i < 2^{60}

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 the value \sum_{i=1}^{N-1}\sum_{j=i+1}^{N} (A_i \mbox{ XOR } A_j), modulo (10^9+7).

Sample Input 1

3
1 2 3

Sample Output 1

6

We have (1\mbox{ XOR } 2)+(1\mbox{ XOR } 3)+(2\mbox{ XOR } 3)=3+2+1=6.

Sample Input 2

10
3 1 4 1 5 9 2 6 5 3

Sample Output 2

237

Sample Input 3

10
3 14 159 2653 58979 323846 2643383 27950288 419716939 9375105820

Sample Output 3

103715602

Print the sum modulo (10^9+7).

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

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

namespace ABC
{
    class ProgramD
    {
        static void Main(string[] args)
        {
            var mod = (long)1e9 + 7;
            var n = long.Parse(Console.ReadLine());
            var list = Console.ReadLine().Split(" ").Select(x => long.Parse(x)).ToList();

            var result = 0L;
            var twoFactor = 1L;
            for (var i = 0; i < 60; i++)
            {
                long even = 0, odd = 0;
                for (var j = 0; j < n; j++)
                {
                    if (((list[j] >> i) & 1) == 1)
                        odd++;
                    else
                        even++;
                }
                var add = (odd * even) % mod * twoFactor % mod;
                result = (result + add) % mod;
                twoFactor = (twoFactor * 2) % mod;
            }

            Console.WriteLine(result);
        }
    }
}