(This question has been seen in the interviews of the following companies: Google)
Implement an iterator to flatten a 2d vector.
Example :Input: 2d vector =
[
[1,2],
[3],
[4,5,6]
]
Output: [1,2,3,4,5,6]
Explanation: By calling next repeatedly until hasNext returns false, the order of elements returned by next should be: [1,2,3,4,5,6].
public class Vector2D implements Iterator {
public Vector2D(List> vec2d) {
}
@Override
public Integer next() {
}
@Override
public boolean hasNext() {
}
}
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