Right Triangles

Description

You are given a 2D boolean matrix grid.

A collection of 3 elements of grid is a right triangle if one of its elements is in the same row with another element and in the same column with the third element. The 3 elements may not be next to each other.

Return an integer that is the number of right triangles that can be made with 3 elements of grid such that all of them have a value of 1.