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#include <cstdio>
#include <set>
#include <cstdint>
#include <cinttypes>
#include <utility>
#include <cassert>

using namespace std;

struct uint128 {
  uint64_t top, low;
  uint128(uint64_t top, uint64_t low) : top(top), low(low) {}
  uint128(uint64_t low) : top(0), low(low) {}
  uint64_t operator%=(uint64_t mod);
  uint128& operator+=(uint64_t a);
  uint128& operator=(const uint128& o);
};
uint128& uint128::operator=(const uint128& o) {
  top = o.top;
  low = o.low;
  return *this;
}

uint128& uint128::operator+=(uint64_t a) {
  uint64_t new_low = low + a;
  if (new_low < low || new_low < a) {
    top++;
  }
  low = new_low;
  return *this;
}
uint64_t uint128::operator%=(uint64_t mod) {
  if (top == 0) {
    low %= mod;
    return low;
  }

  unsigned long long top_mod = 0, low_mod = mod;
  unsigned long long top_x = 0, low_x = 1;
  while ((top > top_mod || (top == top_mod && low >= low_mod)) 
	 && (top_mod & (1ULL << 63)) == 0) {
    // mod  <<= 1
    top_mod = (top_mod << 1) + (low_mod >> 63);
    low_mod <<= 1;
    // x <<= 1
    top_x = (top_x << 1) + (low_x >> 63);
    low_x <<= 1;
  }

  while (top_x != 0 || low_x != 0) {
    if (top > top_mod || (top == top_mod && low >= low_mod)) {
      // res -= mod
      if (low < low_mod) {
	assert(top >= top_mod + 1);
	top--;
      }
      low -= low_mod;
      top -= top_mod;
    }
    // x >>= 1
    low_x = (low_x >> 1) + ((top_x & 1) << 63);
    top_x >>= 1;
    // mod >>= 1
    low_mod = (low_mod >> 1) + ((top_mod & 1) << 63);
    top_mod >>= 1;
  }
  assert(top == 0);
  return low;
}

uint64_t mul_mod(uint64_t a, uint64_t b, uint64_t mod) {
  static const uint64_t MASK_L = (1ULL << 32) - 1;
  a %= mod;
  b %= mod;
  uint64_t top_a = a >> 32, low_a = a & MASK_L, top_b = b >> 32, low_b = b & MASK_L;
  uint64_t top_res = top_a * top_b + ((top_a * low_b + low_a * top_b + ((low_a * low_b)>>32)) >> 32);
  uint64_t low_res = ((top_a * low_b + low_a * top_b) << 32) + low_a * low_b;
  uint128 res(top_res, low_res);
  return (res %= mod);
}

uint64_t fib(uint64_t num) {
  uint64_t modulo = 1000000000000000000ULL;

  uint64_t mask = 1;
  while (mask <= num) {
    mask <<= 1;
  }
  mask >>= 1;
  uint64_t a = 1, b = 0, c = 1;
  while (mask > 0) {
    uint64_t A = (mul_mod(a, a, modulo) + mul_mod(b, b, modulo))%modulo,
      B = (mul_mod(a, b, modulo) + mul_mod(b, c, modulo))%modulo,
      C = (mul_mod(b, b, modulo) + mul_mod(c, c, modulo))%modulo;
    if (num & mask) {
      a = (A + B) % modulo;
      b = A;
      c = B;
    } else {
      a = A;
      b = B;
      c = C;
    }
    mask >>= 1;
  }

  return b;
}

int main() {
  char input[19];
  scanf("%s", input);
  uint64_t num = 0;
  int num_digits = 0;
  while (input[num_digits] != '\0') {
    num = num * 10 + input[num_digits] - '0';
    num_digits++;
  }
  if (num_digits <= 4) {
    uint64_t modulo = 1;
    for (int i = 0; i < num_digits; ++i) {
      modulo *= 10;
    }
    uint64_t a = 0, b = 1;
    set<pair<int, int>> pairs;
    bool put = false;
    int i =0;
    while (true) {
      if (a >= modulo / 10) {
	put = true;
      }
      if (put) {
	if (a == num) {
	  printf("%d\n", i);
	  return 0;
	}
	pair<int, int> p = make_pair(a, b);
	if (pairs.count(p) > 0) {
	  break;
	}
	pairs.insert(p);
      }
      int tmp = a;
      a = b;
      b += tmp;
      b %= modulo;
      i++;
    }
    printf("NIE\n");
    return 0;
  } else {
    const unsigned long long M = 10000000000000000000ULL; 
    uint128 a(0), b(1);
    uint64_t i = 0;
    for (; i < 100; ++i) {
      uint128 A = b;
      b += a.low;
      a = A;
      a %= M;
      b %= M;
    }
    uint64_t mod = 10000;
    for (; i < 16000; ++i) {
      if(a.low % mod == num % mod) {
	break;
      }
      uint128 A = b;
      b += a.low;
      a = A;
      a %= M;
      b %= M;
    }
    if (i == 16000) {
      printf("NIE\n");
      return 0;
    }
    uint64_t mul = 7500;
    for (int d = 5; d <= num_digits; ++d) {
      mod *= 10;
      int j = 0;
      for (; j < 20; ++j) {
	if (fib(i) % mod == num % mod) {
	  break;
	}
	i += mul;
      }
      mul *= 10;
    }
    if (num % 4 == 3 || num % 8 == 0 || num % 4 == 1 || num % 32 == 2) {
      printf("%" PRIu64 "\n", i);
    } else {
      printf("NIE\n");
    }
  }
}