Lexicographically smallest ternary

Numbers from A to B, inclusive, are expressed in the ternary numeral system without leading zeros. Each number is written on a separate line. These lines are then sorted in lexicographical order. Your task is to determine which number appears first in this order.

The numbers A and B are provided in the decimal numeral system, and your answer should also be given in the decimal numeral system.

For instance, if A=2 and B=12, the sequence would be:

In this example, the first number in lexicographical order is 3 (which is represented as 10 in the ternary numeral system).

Input

You are given natural numbers A and B (1 ≤ A ≤ B ≤ 10^15).

Output

Provide the answer to the problem.

Examples