Heapsort. Turns the input array into max
heap and after that sorts it.
Time complexity: O(N log N).
        
        
            
Time complexity: O(N log N).
- Source:
Parameters:
| Name | Type | Description | 
|---|---|---|
| array | Array | Input array. | 
| cmp | function | Optional. A function that defines an alternative sort order. The function should return a negative, zero, or positive value, depending on the arguments. | 
Returns:
- Type:
- 
        
Array
    Sorted array.
    
Example
var sort = require('path-to-algorithms/src' +
'/sorting/heapsort').heapSort;
console.log(sort([2, 5, 1, 0, 4])); // [ 0, 1, 2, 4, 5 ]