Changes

vector <float> ddot(const vector <float>& m1, const vector <float>& m2, const int m1_rows, const int m1_columns, const int m2_columns) {

cudaError_t Error = cudaSuccess;

float* h_p = new float[m1.size()];

float* h_m1 = new float[m1_rows * m1_columns];