Rabbits

import sys

g = (1 + 5**.5) / 2
def fib(N):
    return int((g**N - (1-g)**N) / 5**.5)

MAXN = 481

read = sys.stdin.readline
a, b = map(int, read().split())

def losearch(lo: int, hi: int):
    # print(f"{lo} {hi}")
    if(lo == hi):
        return int(lo)

    len: int = hi-lo    
    mid: int = lo + len//2

    f = fib(mid)

    if (f < a):
        return losearch(mid+1, hi)
    else:
        return losearch(lo, mid)

def hisearch(lo: int, hi: int):
    if(lo == hi):
        return int(lo)

    len: int = hi-lo
    mid: int = lo + len//2

    f = fib(mid)

    if (f < a or f <= b):
        return hisearch(mid+1, hi)
    else:
        return hisearch(lo, mid)

print(hisearch(1, MAXN) - losearch(1, MAXN))

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED