Zigzag Iterator
Given k 1d vectors, implement an iterator to return their elements alternately.
The "Zigzag" order is not clearly defined and is ambiguous fork > 2
cases. If "Zigzag" does not look right to you, replace "Zigzag" with "Cyclic". For example:
Input:
[1,2,3]
[4,5,6,7]
[8,9]
Output:
[1,4,8,2,5,9,3,6,7].
Uses a linkedlist to store the iterators in different vectors. Every time we call next(), we pop an element from the list, and re-add it to the end to cycle through the lists.
public class ZigzagIterator {
LinkedList<Iterator> list;
public ZigzagIterator(List<Integer> v1, List<Integer> v2) {
list = new LinkedList<Iterator>();
if (!v1.isEmpty()) {
list.add(v1.iterator());
}
if (!v2.isEmpty()) {
list.add(v2.iterator());
}
}
public int next() {
Iterator it = list.remove();
int res = (Integer)it.next();
if (it.hasNext()) {
list.add(it);
}
return res;
}
public boolean hasNext() {
return !list.isEmpty();
}
}
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