#include <iostream>
 
void swapPointers(double** num1, double** num2) {
  double* temp = *num1;
  *num1 = *num2;
  *num2 = temp;
}
 
int main() {
    double a = 1.0f;
    double b = 5.0f;
    double* pa = &a;
    double* pb = &b;
    swapPointers(&pa, &pb);
    std::cout << *pa << " " << *pb << std::endl;
    std::cout << a << " " << b << std::endl;
}