There is an integer array $\boldsymbol{d}$ which does not contain more than two elements of the same value. How many distinct ascending triples ($d[i]<d[j]<d[k],i<j<k$) are present? 

Input format

The first line contains an integer, $N$, denoting the number of elements in the array. This is followed by a single line, containing $N$ space-separated integers. Please note that there are no leading spaces before the first number, and there are no trailing spaces after the last number.

Output format:

A single integer that denotes the number of distinct ascending triplets present in the array.

Constraints:

$N\leq10^5$

Every element of the array is present at most twice.

Every element of the array is a 32-bit non-negative integer.

Sample input:

6
1 1 2 2 3 4

Sample output:

4

Explanation

The distinct triplets are

(1,2,3)

(1,2,4)

(1,3,4)

(2,3,4)

The elements of the array might not be sorted. Make no assumptions of the same.

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