vector <float> dot (const vector <float>& m1, const vector <float>& m2, const int m1_rows, const int m1_columns, const int m2_columns) { /* Returns the product of two matrices: m1 x m2. Inputs: m1: vector, left matrix of size m1_rows x m1_columns m2: vector, right matrix of size m1_columns x m2_columns (the number of rows in the right matrix must be equal to the number of the columns in the left one) m1_rows: int, number of rows in the left matrix m1 m1_columns: int, number of columns in the left matrix m1 m2_columns: int, number of columns in the right matrix m2 Output: vector, m1 * m2, product of two vectors m1 and m2, a matrix of size m1_rows x m2_columns */