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 Ruby (2.3.3) (judge verdict: Accepted)

eval'N,*A='+`dd`.split*?,
f=->a{l=[[0,i=-1]]
a.map{|x|l.pop while(t=l[-1])[0]>x
l<<[x,i+=1]
i-t[1]}}
r=0
A.zip(f[A],f[A.reverse].reverse){|a,b,c|r+=a*b*c}
p r