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Given an unsorted array **arr[] **of **n** positive integers. Find the number of triangles that can be formed with three different array elements as lengths of three sides of triangles.

**Example 1:**

**Input**:
n = 3
arr[] = {3, 5, 4}
**Output**:
1
**Explanation**:
A triangle is possible
with all the elements 5, 3 and 4.

**Example 2:**

**Input**:
n = 5
arr[] = {6, 4, 9, 7, 8}
**Output**:
10
**Explanation**:
There are 10 triangles
possible with the given elements like
(6,4,9), (6,7,8),...

**Your Task: **

This is a function problem. You only need to complete the function **findNumberOfTriangles****() **that takes **arr[] **and** n** as input parameters and returns** **the count of total possible triangles.

**Expected Time Complexity: **O(n^{2}).

**Expected Space Complexity: **O(1).

**Constraints:**

3 <= n <= 10^{3}

1 <= arr[i] <= 10^{3}

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Count the number of possible triangles

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