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#include <cstdlib>
#include <iostream>
#include <vector>
using namespace std;

typedef unsigned long long ULL;

const ULL M=ULL(1000*1000*1000)*ULL(1000*1000*1000);

ULL mul_mod (ULL a, ULL b)
{
  ULL wyn = 0;
  a%=M;
  b%=M;
  for (; b; a<<=1, b>>=1)
  {
    if (a>=M)
      a-=M;
    if (b&1)
    {
      wyn+=a;
      if (wyn>=M)
        wyn-=M;
    }
  }
  return wyn;
}

class fib_num
{
  public:
  fib_num()
  : num(0)
  , vals{{0, 0}, {0, 0}}
  {}
  fib_num(int w)
  {
    if (w == 0)
    {
      num = 0;
      vals[0][0] = vals[1][1] = 1;
      vals[1][0] = vals[0][1] = 0;
    }
    else if (w == 1)
    {
      num = 1;
      vals[0][0] = 0;
      vals[1][0] = vals[0][1] = vals[1][1] = 1;
    }
    else
    {
      throw;
    }
  }
  fib_num operator+(const fib_num& b)
  {
    fib_num w;
    w.num = this->num+b.num;
    w.vals[0][0] = mul_mod(this->vals[0][0], b.vals[0][0]) + mul_mod(this->vals[0][1], b.vals[1][0]);
    w.vals[0][1] = mul_mod(this->vals[0][0], b.vals[0][1]) + mul_mod(this->vals[0][1], b.vals[1][1]);
    w.vals[1][0] = mul_mod(this->vals[1][0], b.vals[0][0]) + mul_mod(this->vals[1][1], b.vals[1][0]);
    w.vals[1][1] = mul_mod(this->vals[1][0], b.vals[0][1]) + mul_mod(this->vals[1][1], b.vals[1][1]);
    return w;
  }
  void describe ()
  {
    printf("matrix no %lld:\n", num);
    printf("%lld\t%lld\n%lld\t%lld\n", vals[0][0], vals[0][1], vals[1][0], vals[1][1]);
  }
  ULL num;
  ULL vals[2][2];
};

ULL pow10[30];
int digits[30];
int n = 0;

int k_digit (ULL num, int k)
{
  return (num/pow10[k-1])%10;
}

void find_num (fib_num mult, fib_num reminder, int digit_no)
{
  if (digit_no > n)
  {
    if (reminder.vals[0][1] < pow10[n-1])
      return;
    printf("%lld\n", reminder.num);
    exit(0);
  }
  int
    first  = k_digit(reminder.vals[0][1], digit_no),
    second = k_digit(reminder.vals[1][1], digit_no);

  fib_num new_mult = 0;
  fib_num acc = new_mult+reminder;

  int
    c_first  = k_digit(acc.vals[0][1], digit_no),
    c_second = k_digit(acc.vals[1][1], digit_no);

  vector<fib_num> next_layer;

  int q=0;
  while (true)
  {
    q++;
    if (c_first == digits[digit_no])
      next_layer.push_back(acc);

    new_mult = new_mult+mult;
    acc = new_mult + reminder;

    c_first  = k_digit(acc.vals[0][1], digit_no),
    c_second = k_digit(acc.vals[1][1], digit_no);

    if (c_first == first && c_second == second)
      break;
  }

  for (auto e : next_layer)
    find_num(new_mult, e, digit_no+1);
}

int main ()
{
  string s;
  cin>>s;
  for (int i=s.size()-1; i>=0; i--)
    digits[1+n++] = s[i]-'0';
  pow10[0] = 1;
  for (int i=1; i<=n; i++)
    pow10[i]=pow10[i-1]*10;
  find_num(fib_num(1), fib_num(0), 1);
  printf("NIE\n");
	return 0;
}