Problem D. Pashmak and Parmida's problem

时间限制 3000 ms   内存限制 256 MB

Parmida is a clever girl and she wants to participate in Olympiads this year. Of course she wants her partner to be clever too (although he's not)! Parmida has prepared the following test problem for Pashmak.

There is a sequence a that consists of n integers a1, a2, ..., an. Let's denote f(l, r, x) the number of indices k such that: l ≤ k ≤ r and ak = x. His task is to calculate the number of pairs of indicies i, j(1 ≤ i < j ≤ n) such that f(1, i, ai) > f(j, n, aj).

Help Pashmak with the test.

输入数据

The first line of the input contains an integer n(1 ≤ n ≤ 106). The second line contains n space-separated integers a1, a2, ..., an(1 ≤ ai ≤ 109).

输出数据

Print a single integer — the answer to the problem.

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