Implement class Sorter with next methods:

constructor - creates instance of Sorter class

add - add element and store it in any way inside

length - return the count of current elements, which were added to Sorter instance via add method

toArray - return all elements in array. For example:

  const sorter = new Sorter();
  sorter.add(1);
  sorter.add(2);

  console.log(sorter.length) // 2
  console.log(sorter.toArray()) // [1, 2]

sort - takes indices of already added elements and sorts only these elements. For example:

  const sorter = new Sorter();
  sorter.add(2);
  sorter.add(1);

  console.log(sorter.length) // 2
  console.log(sorter.toArray()) // [2, 1]

  sorter.sort([0, 1]);
  console.log(sorter.toArray()) // [1, 2]

setComparator - takes compareFunction as parameter and use it while sorting elements. You can read about compareFunction here. Sort should work for numbers by default (if compareFunction was not set directly using this method) For example:

  const sorter = new Sorter();
  sorter.add(2);
  sorter.add(1);

  sorter.sort([0, 1]);
  console.log(sorter.toArray()) // [1, 2]

  sorter.add(3);

  const reverseCompareFunction = (left, right) => right - left;
  sorter.setComparator(reverseCompareFunction);

  sorter.sort([0, 1, 2]);
  console.log(sorter.toArray()); // [3, 2, 1]

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

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