how to find 2d vector length cpp

1myVector[
2  Vector[0, 4, 2, 5],
3  Vector[1, 4, 2]
4];
5
6/*When you call for myVector[1].size() it would return 3 and [0] would return 4.
7
8For the amount of rows (int vectors) in the 2d vector, you can just use myVector.size()
9
10You can run this to see it in actions*/