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It is required to find out whether it is possible to delete given files from MS-DOS directory executing the DEL command of MS-DOS operation system only once. There are no nested subdirectories.
A note
DEL command has the following format: DEL wildcard
The actual wildcard as well as a full file name can be made up either of a name containing 1 up to 8 characters or of a name and extension, containing up to 3 characters. The point character "." separates the extension from the file name. The extension can be empty and this is equivalent to a name without any extension (in this case a wildcard ends with a point). In a wildcard the characters "?" and "*" can be used. A question mark substitutes exactly one character of the full file name excluding a point, an asterisk - any sequence of characters (containing no points) even empty one. An asterisk can appear only at the last position of the name and the extension.
MS-DOS system can permit maybe other wildcards but they can not be used in this task. File names and extensions consist only of Latin capitals and digits.
Input data
In the first line of input there is one positive integer denoting number of sets of file names. Each set contains a list of full file names without spaces (names without extenstion don't have to be finished with a dot). Each name is written in separate line and preceded with a control sign: "-" for delete or "+" for keep. Full file names are not repeated. The list comprises at least one file, at least one file is marked to be deleted, and there are no more than 1000 files in a set. The last line of a set is empty and should not be treated as a file name.
Output data
For each set write a single line containing the required DEL command (only one proposal) or word IMPOSSIBLE if there is no solution. A single space should separate "DEL" from wildcard.
Input data example:
2 +A.CPP -B.CPP -C.CPP -BP.EXE -BPC.EXE +TURBO.EXE
Possible output data for our example:
IMPOSSIBLE DEL ?P*.*