Class NestedIterator
- All Implemented Interfaces:
java.util.Iterator<java.lang.Integer>
Medium
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 listnestedList
.int next()
Returns the next integer in the nested list.boolean hasNext()
Returnstrue
if there are still some integers in the nested list andfalse
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
[-106, 106]
.
-
Constructor Summary
-
Method Summary
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface java.util.Iterator
forEachRemaining, remove
-
Constructor Details
-
NestedIterator
-
-
Method Details
-
next
public java.lang.Integer next()- Specified by:
next
in interfacejava.util.Iterator<java.lang.Integer>
-
hasNext
public boolean hasNext()- Specified by:
hasNext
in interfacejava.util.Iterator<java.lang.Integer>
-