Given a string s represents the serialization of a nested list, implement a parser to deserialize it and return the deserialized NestedInteger.

Each element is either an integer or a list whose elements may also be integers or other lists.

Example 1:

Input: s = "324"
Output: 324
Explanation: You should return a NestedInteger object which contains a single integer 324.

Example 2:

Input: s = "[123,[456,[789]]]"
Output: [123,[456,[789]]]
Explanation: Return a NestedInteger object containing a nested list with 2 elements:
1. An integer containing value 123.
2. A nested list containing two elements:
    i.  An integer containing value 456.
    ii. A nested list with one element:
         a. An integer containing value 789

Constraints:

• 1 <= s.length <= 5 * 104
• s consists of digits, square brackets "[]", negative sign '-', and commas ','.
• s is the serialization of valid NestedInteger.
• All the values in the input are in the range [-106, 106].