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# Zigzag Iterator

Given two 1d vectors, implement an iterator to return their elements alternately.

**Example:**

```
Input:
v1 = [1,2]
v2 = [3,4,5,6] 

Output: [1,3,2,4,5,6]

Explanation: By calling next repeatedly until hasNext returns false, 
             the order of elements returned by next should be: [1,3,2,4,5,6].
```

**Follow up**: What if you are given`k`1d vectors? How well can your code be extended to such cases?

**Clarification for the follow up question:**\
The "Zigzag" order is not clearly defined and is ambiguous for`k > 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].
```

## Solution

```
public class ZigzagIterator {

    public ZigzagIterator(List<Integer> v1, List<Integer> v2) {

    }

    public int next() {

    }

    public boolean hasNext() {

    }
}

/**
 * Your ZigzagIterator object will be instantiated and called as such:
 * ZigzagIterator i = new ZigzagIterator(v1, v2);
 * while (i.hasNext()) v[f()] = i.next();
 */
```