Pythagorean Triplet in an array

Given an array of integers, write a function that returns true if there is a triplet (a, b, c) that satisfies a^2+ b^2= c^2.

Example:

Input: arr[] = {3, 1, 4, 6, 5}
Output: True
There is a Pythagorean triplet (3, 4, 5).

Input: arr[] = {10, 4, 6, 12, 5}
Output: False
There is no Pythagorean triplet.