New to Perl

[nos]

I am looking for a way to look into a file and determine the next
number in a sequence that is not present within a range of numbers.
Example:
File 10000
10001
10003
10004

I want it to find 10002 as the missing number. Any suggestions.

Thanks,
Nos

 

[John W. Krahn]

I am looking for a way to look into a file and determine the next
number in a sequence that is not present within a range of numbers.
Example:
File 10000
10001
10003
10004

I want it to find 10002 as the missing number. Any suggestions.

perl -lne'print for $last + 1 .. $_ - 1; $last = $_' yourfile



John

 

[Mark]

I am looking for a way to look into a file and determine the next
number in a sequence that is not present within a range of numbers.
Example:
File 10000
10001
10003
10004

I want it to find 10002 as the missing number. Any suggestions.

Thanks,
Nos

Well you could just subtract each number from the next. If the answer is
<> -1 your have a gap.

 

[Tad McClellan]

Any suggestions.

I suggest putting the subject of your article in the Subject
of your article.

Your post was *not* about being new to Perl.

 

[Bob]

perl -lne'print for $last + 1 .. $_ - 1; $last = $_' yourfile
John

c:\tmp> perl -lne'print for $last + 1 .. $_ - 1; $last = $_' data

where data is file with 4 lines..
10001
10003
10004
10005

on w2k sp2 system - I get following error msg
Can't find string terminator "'" anywhere before EOF at -e line 1.

 

[Sam Holden]

c:\tmp> perl -lne'print for $last + 1 .. $_ - 1; $last = $_' data

where data is file with 4 lines..
10001
10003
10004
10005

on w2k sp2 system - I get following error msg
Can't find string terminator "'" anywhere before EOF at -e line 1.

perldoc -q one-liner

Why don't Perl one-liners work on my DOS/Mac/VMS system?

 

[John W. Krahn]

c:\tmp> perl -lne'print for $last + 1 .. $_ - 1; $last = $_' data

where data is file with 4 lines..
10001
10003
10004
10005

on w2k sp2 system - I get following error msg
Can't find string terminator "'" anywhere before EOF at -e line 1.

Sorry, I don't use Windows, but my understanding from reading the Perl
documentation is that you have to use " instead of ' when running on
Windows.

perl -lne"print for $last + 1 .. $_ - 1; $last = $_" data


John

 

[Bob]

perldoc -q one-liner

Why don't Perl one-liners work on my DOS/Mac/VMS system?

that explains why perldoc -q terminator or perldoc -q EOF or a host of
other perldoc inquiries did not provide me with an answer.
thanks

 

[Bob]

Sorry, I don't use Windows, but my understanding from reading the Perl
documentation is that you have to use " instead of ' when running on
Windows.

perl -lne"print for $last + 1 .. $_ - 1; $last = $_" data


John

thanks. that works.. ( in a way).. starts at 1