Products of matrices P88905

Statement

Write a function that, given two matrices @a@ and @b@, computes their product.

Interface

C++	`typedef vector< vector<int> > Matrix; Matrix product(const Matrix& a, const Matrix& b);`
MyPy	`Matrix: TypeAlias = list[list[int]] def product(a: Matrix, b: Matrix) -> Matrix`

@a@ is a matrix $p\times q$ and @b@ is a matrix $q\times r$ , with $p,q,r\ge1$ .

Information