Lucky Numbers

Time Limit : 2 Second

Memory Limit : 64 MB

Submission: 436

Solved: 124

Description
Isun loves digit 4 and 8 very much. He thinks a number is lucky only if the number satisfy the following conditions:

1.       The number only consists of digit 4 and 8.

2.       The number multiples 48.

One day, the math teacher gives Isun a problem:

         Given L and R(1 <= L <= R <= 10^15), how many lucky numbers are there between L and R. (i.e. how many x satisfy L <= x <= R, x is a lucky number).

Input
Multiple test cases. For each test case, there is only one line consist two numbers L and R.

Output
For each test case, print the number of lucky numbers in one line.

 

Do use the %lld specifier or cin/ cout stream to read or write 64-bit integers in С++.

sample input
1 48
1 484848
sample output
1
7
hint


source
Problem Setter : Yang Xiao
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