// Unsafe code example
// run with valgrind -q a.out 
#include<iostream>
int & get_number()
{
  int n1 = 100;
  int & r_n1 = n1; 
  return r_n1;
}
int main()
{
  int number = get_number();
  std::cout<<"number is "<<number<<"\n";
}