Ответ:

#include <iostream>

#include <ctime>

using namespace std;

int main()

{

srand(time(NULL));

int n;

double sum = 0;

double multiply = 1;

cout << "Enter n = ";

cin >> n;

double *mas = mas = new double[n];

for (int i = 0; i < n; ++i)

{

 mas[i] = -50 + (double)(rand() % 10001) / 100;

 cout << mas[i] << " ";

}

for (int i = 0; i < n; i++)

{

 if (mas[i] < 0)

  multiply *= mas[i];

 else

  sum += mas[i];

}

cout << "sum positive = " << sum << endl;

cout << "multiply negative = " << multiply << endl;

system("pause");

}

Объяснение: