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## Learning Opportunities

This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.

## Goal

You have to fill in all the unknown digits in a multiplication.
These unknown digits are marked as stars * in the operation.
Note that the numbers involved never begin with a zero, excepted when a line is null.
* For example, 234 is possible everywhere.
* 00 is accepted but only as a full line in a partial result.
* 0234 is not possible, neither as operand, partial result or result.

The multiplication symbol is an x.
The stars may appear everywhere in the operation:
* In the operands, in the partial results or in the result.
* In only one of the three, in two or three of them.

In the partial results, the first line has got no trailing zeroes (but might end by zero if you multiply 5×48). The second line has got one trailing zero, the second line has got two trailing zeroes, and so on. Why?
Because if you calculate 907×757, in fact, the operation is shown as 907×(7+50+700)=907×7 [first line] + 907×50 [second line] + 907×700 [third line]. Thus, the operation must be shown as:
`   907x  757------  6349 → 7×907 45350 → 50×907634900 → 700×907------686599`

And not as:
`   907x  757------  6350 → 50×907 45349 → 7×907634900 → 700×907------686599`
Input
Line 1: The number n of lines of the operation
Next n lines: The holey multiplication
Output
Write the input but with the stars replaced with digits.
No star shall be left.
Constraints
There is only one solution.
Example
Input
```6
25
x  *
----
175
----
175```
Output
```  25
x  7
----
175
----
175```

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