//passage des variables par pointeur
#include <iostream>

using namespace std;

//passage par pointeur
void swap(int *n1, int *n2);

int main() {
  int a = 10;
  int b = 20;
  cout << "avant swap : " << n1 << " " << n2 << endl;
  swap(&a, &b);
  cout << "apres swap : " << n1 << " " << n2 << endl;

  return 0;
}

void swap(int *n1, int *n2) {
  int temp = *n1;   
  *n1 = *n2;
  *n2 = temp;
  cout << "dans swap : " << *n1 << " " << *n2 << endl;
}