size of 2d matrix c++ code example

Example 1: length of 2d array c++

int rows = sizeof(arr) / sizeof(arr[0]); // returns rows
int col = sizeof(arr[0]) / sizeof(int); // returns col

Example 2: how to get size of 2d vector in c++

myVector[
  Vector[0, 4, 2, 5],
  Vector[1, 4, 2]
];

/*When you call for myVector[1].size() it would return 3 and [0] would return 4.

For the amount of rows (int vectors) in the 2d vector, you can just use myVector.size()

You can run this to see it in actions*/