convert an array to a string Overrides Object.toString()
A string representation of array.
If this method is invoked on an object that is not an Array.
toString() converts an array to a string by first converting each array element to strings (by calling its toString()method). Once each element is converted to a string, toString()outputs them in a comma-separated list. This return value is the same string that would be returned by the join() method with no arguments.