I want a regular expression that checks that a string has only 4 digits at the end & starts with "aaa_", inbetween string can have digits,alphabets and underscore{1,24} .

I tried with
$test = "00000"; if($test =~ /^aaa_[a-z0-9_]{1,24}[0-9]{4,4}$/){
print "Match---\n";
}
else{
print "No Match... :(\n";
}

But this says its a match.

Please provide a regexp that says:
Match for "aaa_gjh1_dfgdf_0009","aaa_gjh_0000"
No Match for "aaa_fdsfs_000", "aaa_sdf_jdsh_01111".

i.e. allows ONLY 4 digits at the end of a string

In reply to Number of digits at the end of the string by isha

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