количество циклических сдвигов

#include <iostream>
#include <cmath>
using namespace std;

void poisk (int raznica, int left, int right)
{
 int i=(right + left)/2;
 int middle = 0;

  cout << "?" << " " << i << endl;
  cin >> middle;

  int tek_raznica = middle - i;

  if (tek_raznica < raznica)
    {
      right = i;
      if (right - left == 1)
       cout << "!" << " " << left << endl;
      else
        poisk (raznica, left, right);
    }
  if (tek_raznica >= raznica)
    {
      left = i;
      if (right - left == 1)
        cout << "!" << " " << left << endl;
      else
        poisk (raznica, left, right);
      }

}
int main()
  {
    cout.flush();
    int n=0,  elem_first;
    cin >> n;

    cout << "?" << " " << 1 << endl;
    cin >> elem_first;
    int raznica = elem_first-1;

    poisk(raznica, 1, n);

  }