// CSE 143 Sp 01 Homework 2.5
// Programming question sample solution
// HP  4/01

#include <iostream>
using namespace std;


// = a1*b1 + a2*b2 + ... + an*bn (origin 1 vectors)
double dotProduct(double a[], double b[], int n) {
	double result = 0.0;
	for (int k = 0; k < n; k++) {
		result = result + a[k]*b[k];
	}
	return result;
}

// = new vector containing [a1+b1, a2+b2, + ... + an+bn]
double *vectorSum(double a[], double b[], int n) {
	double *result = new double[n];
	for (int k = 0; k < n; k++) {
		result[k] = a[k] + b[k];
	}
	return result;
}

// print vector v with n elements
// assumption: n > 0
void printVector(double v[], int n) {
	cout << "[" << v[0];
	for (int k = 1; k < n; k++) {
		cout << ", " << v[k];
	}
	cout << "]";
}


// read n and two vectors of length n
// print the vectors, their dot product, and their sum,
int main() {
	int		n;			// vector lengths
	double *v, *w;		// input vectors
	double *sum;		// vector sum v+w
	double	dotprod;	// dot product
	int		k;

	// allocate and read vectors
	cout << "Please enter vector length: ";
	cin >> n;

	v = new double[n];
	w = new double[n];

	cout << "enter " << n << " numbers for first vector: ";
	for (k = 0; k < n; k++)
		cin >> v[k];

	cout << "enter " << n << " numbers for second vector: ";
	for (k = 0; k < n; k++)
		cin >> w[k];
	
	// calculate results and print everything
	dotprod = dotProduct(v,w,n);
	sum = vectorSum(v,w,n);

	cout << "First vector:   ";
	printVector(v,n);
	cout << "\nSecond vector : ";
	printVector(w,n);
	cout << "\nDot product = " << dotprod;
	cout << "\nVector sum  = ";
	printVector(sum,n);
	cout << endl;

	// delete dynamic storage
	delete [] v;
	delete [] w;
	delete [] sum;

	return 0;
}