Read up on the map function.

Evaluates the BLOCK or EXPR for each element of LIST (locally setting 
+$_ to each element) and returns the list value composed of the result
+s of each such evaluation. 

In scalar context, returns the total number of elements so generated. 

Evaluates BLOCK or EXPR in list context, so each element of LIST may p
+roduce zero, one, or more elements in the returned value.
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