Multiplication

Interview

Time limit2sMemory limit1024 MB

Summary

Count the triples i < j < k with A[i] * A[j] = A[k] in an array of at most 100 positive integers.

Level: Easy3 of 10
Topics: Brute force, Array, Implementation
Solved: No attempts yet

Problem

Aoi, a student at JOI High School, found a scroll in the library. The scroll has N integers written in a row, and the i-th number from the left (1 ≦ i ≦ N) is Ai.

Looking at the scroll, Aoi wondered: "If I choose 3 of these N integers and call them x, y, z in order from left to right, how many ways are there to choose integers such that x × y = z?"

Given the N integers written on the scroll, write a program to find the answer to Aoi's question.

Input

The input is given from standard input in the following format.

N
A1 A2 … AN

Output

Print the answer to Aoi's question to standard output in 1 line.

Constraints

3 ≦ N ≦ 100.
1 ≦ Ai ≦ 999 (1 ≦ i ≦ N).
All input values are integers.

Examples4

Example 1
Input
```
3
21 13 273
```
Expected output
```
1
```
Example 2
Input
```
3
10 5 2
```
Expected output
```
0
```
Example 3
Input
```
5
4 2 2 8 16
```
Expected output
```
4
```
Example 4
Input
```
10
1 1 1 1 1 1 1 1 1 1
```
Expected output
```
120
```