Problem:
Score : 400 points

Problem Statement

One day, Snuke was given a permutation of length N, a_1, a_2, ..., a_N, from his friend.

Find the following:

Constraints

1 ≦ N ≦ 200,000

(a_1, a_2, ..., a_N) is a permutation of (1, 2, ..., N).

Input

The input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

Print the answer.

Note that the answer may not fit into a 32-bit integer.

Sample Input 1

3
2 1 3

Sample Output 1

9

Sample Input 2

4
1 3 2 4

Sample Output 2

19

Sample Input 3

8
5 4 8 1 2 6 7 3

Sample Output 3

85

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

using System;
using System.Linq;

namespace agc005_b
{
	class Program
	{
		static void Main(string[] args)
		{
			int n = int.Parse(Console.ReadLine());
			int[] x = Console.ReadLine().Split().Select(int.Parse).ToArray();
			long ret = 0;
			for (int i = 0; i < n; i++)
			{
				long multiply = 1;
				int j = 0;
				while (0 <= i - j && x[i - j] >= x[i]) j++;
				multiply *= j;
				j = 0;
				while (i + j < n && x[i] <= x[i + j]) j++;
				multiply *= j;
				ret += x[i] * multiply;
			}
			Console.WriteLine(ret);
		}
	}
}