You are given a nested list of integers `nestedList`

. Each element is either an integer or a list whose elements may also be integers or other lists. Implement an iterator to flatten it.

Implement the `NestedIterator`

class:

`NestedIterator(List<NestedInteger> nestedList)`

Initializes the iterator with the nested list`nestedList`

.`int next()`

Returns the next integer in the nested list.`boolean hasNext()`

Returns`true`

if there are still some integers in the nested list and`false`

otherwise.

Your code will be tested with the following pseudocode:

initialize iterator with nestedList res = [] while iterator.hasNext() append iterator.next() to the end of res return res

If `res`

matches the expected flattened list, then your code will be judged as correct.

**Example 1:**

Input:nestedList = [[1,1],2,[1,1]]Output:[1,1,2,1,1]Explanation:By calling next repeatedly until hasNext returns false, the order of elements returned by next should be: [1,1,2,1,1].

**Example 2:**

Input:nestedList = [1,[4,[6]]]Output:[1,4,6]Explanation:By calling next repeatedly until hasNext returns false, the order of elements returned by next should be: [1,4,6].

**Constraints:**

`1 <= nestedList.length <= 500`

- The values of the integers in the nested list is in the range
`[-10`

.^{6}, 10^{6}]