Special numbers

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Problem

Special numbers are positive integers whose decimal representation contains only the special digits $2$ and $5$ . For example, $25,\ 522,\ and\ 2$ are the special numbers and $7,\ 15,\ and\ 265$ are not.
Assume that $f(k)$ is the smallest special number that is greater than or equal to $k$ . Determine the value of the following expression for a pair $(l,r)$ :
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Input format

First line: An integer $T$ denoting the number of test cases
Next $T$ lines: Two integers $l$ and $r$

Output format
For each test case, print the required answer.

Constraints
$1 ≤ T ≤ 50\\ 1 ≤ l ≤ r ≤ 10^9$

Time Limit: 1

Memory Limit: 256

Source Limit:

Explanation

In the first sample:
f(3)+f(4)+f(5)+f(6)+f(7)=5+5+5+22+22=59