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 Kotlin (1.0.0) (judge verdict: Runtime Error)

import java.math.BigInteger;
import java.util.*;
object MainKt {
  @JvmStatic fun main(args:Array<String>) {
  val N:Int=readLine()!!.toInt()
  val sc=Scanner(System.`in`)
  val a=Array(N) {sc.nextInt()}
  // a.forEach {println(it)}
  println((1..N).fold(BigInteger("0")) {
    sum:BigInteger,l:Int -> sum + (l..N).fold(BigInteger("0")) {
      part:BigInteger,r:Int -> 
      val s=((l-1)..(r-1)).map{a[it]}.min()
      part + BigInteger("${s}")
    }
  })
  }
}