You can achieve your desired output by using this re: 
$a =~/^(.+)(e|r)?(.*)$/;

[download]
Update: Just noticed - this is almost the same as choroba's suggestion.

        ...it is unhealthy to remain near things that are in the process of blowing up.     man page for WARP, by Larry Wall

In reply to Re: Basic Regular expression by NetWallah
in thread Basic Regular expression by skkeni04

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