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CF1107B.Digital root
Digital root
Today at the lesson of mathematics, Petya learns about the digital root.
The digital root of a non-negative integer is the single digit value obtained by an iterative process of summing digits, on each iteration using the result from the previous iteration to compute a digit sum. The process continues until a single-digit number is reached.
Let's denote the digital root of as . Then , , .
As a homework Petya got tasks of the form: find -th positive number whose digital root is .
Petya has already solved all the problems, but he doesn't know if it's right. Your task is to solve all tasks from Petya's homework.
Input
The first line contains a single integer () — the number of tasks in Petya's homework. The next lines contain two integers () and () — -th Petya's task in which you need to find a -th positive number, the digital root of which is .
Output
Output lines, -th line should contain a single integer — the answer to the -th problem.
Samples
3
1 5
5 2
3 1
5
38
19
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