Love triangles

History

Spichonees (made-up name) live in country Spichland where are no gender. Spichonees are big lovers, so each Spichonee loves any another Spichonee. Unfortunately there are sometimes situations, when Spichonee A loves Spichonee B, Spichonee B loves Spichonee C and Spichonee C loves Spichonee A. This phenomenon is called Love triangle.

Task

Your task is to implement function getLoveTrianglesCount which calculates how many love triangles phenomenons take place. The function takes the array of integers as the only parameter. An integer k on nth place means, that nth Spichonee loves kth Spichonee.

For example:

                                  // 1  2  3  Spichonees
  let count = getLoveTrianglesCount([2, 3, 1]);
  console.log(count); // 1
  /**
    1st Spichonee loves 2nd Spichonee.
    2nd Spichonee loves 3rd Spichonee.
    3rd Spichonee love 1st Spichonee.
    There is love triangle.
  */

Write your code in `src/index.js. Be sure, that all tests are positive. That means you cannot catch any error in tests.

Prepare and test

• Install Node.js
• Clone this repository: git clone https://github.com/yankouskia/love-triangle.git
• Go to folder love-triangle
• Run npm install in command line
• Run npm test in command line
• You will see the number of passing and failing tests