Rabbits

import math

R1 = (1 - 5**0.5) / 2
R2 = (1 + 5**0.5) / 2

BETA = (1 - math.exp(R1)) / (math.exp(R2) - math.exp(R1))
ALPHA = 1 - BETA

def f(n):
    return ALPHA * math.exp(R1 * n) + BETA * math.exp(R2 * n)

a, b = [ int(e) for e in input().split() ]
n = 0

while not (a <= 2 * f(n) <= b):
    n += 1

print(n)

"""
# a, b = [ int(e) for e in input().split() ]

pairs = 1
month = 0
incoming_pairs = 0

print(R1**R1 - R1 - 1)

while not (a <= 2 * pairs <= b):
    month += 1
    q = pairs
    pairs += incoming_pairs
    incoming_pairs = q

print(month)
"""

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 3

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 4

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 5

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 6

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 9

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 10

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 11

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 14

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 15

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 16

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 17

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 18

Verdict: WRONG ANSWER

Test 19

Verdict: WRONG ANSWER

Test 20

Verdict: WRONG ANSWER

Test 21

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 22

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...

Test 23

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 15, in <module>
    while...