#include <iostream>

using namespace std;

void spaces(int n)
{ for (int i = 0; i < n; i += 1)
    cout << "   "; }

struct tracer
{ int param;

  static int depth;

  tracer(int p)
  { param = p;
    depth += 1;
    spaces(depth);
    cout << "function called with parameter " << param << "\n"; }

  ~tracer()
  { spaces(depth);
    cout << "function with parameter " << param << " exitted\n";
    depth -= 1; }
};

int tracer::depth = 0;

void f(int x)
{ tracer o(x);
  int q = x / 10, r = x % 10;
  if (q > 0)
    f(q);
  cout << r << "\n";
  if (q > 0)
    f(q); }

int main()
{ f(47282);
  cout << "\n"; }