I am trying to write a program with a function double_product(vector<double> a, vector<double> b) that computes the scalar product of two vectors. The scalar product is $a_{0}b_{0}+a_{1}b_{1}+...+a_{n-1}b_{n-1}$. Here is what I have. It is a mess, but I am trying! #include <iostream> #include <vector> using namespace std; class Scalar_product { public: Scalar_product(vector<double> a, vector<double> b); }; double scalar_product(vector<double> a, vector<double> b) { double product = 0; for (int i = 0; i <= a.size()-1; i++) for (int i = 0; i <= b.size()-1; i++) product = product + (a[i])*(b[i]); return product; } int main() { cout << product << endl; return 0; }