Rabbits

#include <bits/stdc++.h>

using namespace std;

/*
Far far away in the future, humanity has sent 1 frozen newborn rabbit pair to populate an alien planet. Each pair of rabbits reaches maturity at the age of 1 month and they immediately mate. One month after mating the pair reproduces one pair of rabbits, after which the older pair mates again immediately. The rabbits never die and continue breeding forever.
How many months will the rabbit population be in an interval between a and b?
Input:
The first line contains 2 integers a,\,b: the interval boundaries.
Output:
Print a single integer d: the duration (in months) when the number of rabbit pairs is in the interval [a,\,b] inclusive.

Constraints:
1 \leq a \leq b \leq 10^{100}*/

long long fibonacci (long long i) {
  if (i == 0)
    return 0;
  if (i == 1)
    return 1;
  return fibonacci (i - 1) + fibonacci (i - 2);
}

int main()
{
    // ios_base::sync_with_stdio(0);
    // cin.tie(0);

    int a, b;
    cin >> a >> b;

    if (a <=2 )
        cout << 1;
    else {
        long long fib1 = 1;
        long long fib2 = 2;

        while (fib2 < a) {
            long long temp = fib2;
            fib2 = fib1 + fib2;
            fib1 = temp;
        }
        if (fib2 > b) {
            cout << 0 << endl;
        }
        else {
            long long count = 0;
            while (fib2 <= b) {
                ++count;
                long long temp = fib2;
                fib2 = fib1 + fib2;
                fib1 = temp;
            }
            cout << count << endl;
        }
    }
}

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: WRONG ANSWER

Test 14

Verdict: ACCEPTED

Test 15

Verdict: WRONG ANSWER

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: WRONG ANSWER

Test 19

Verdict: WRONG ANSWER

Test 20

Verdict: WRONG ANSWER

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED