Re^2: adding 1 to a char of 1

Thanks everyone for your help, it works fine now.... One last question.... now that I have the correct number, how do I only grab the last 4 digits so for example:

my original number was 9 but now with the code u guys gave me, we incr
+emented into 10. I need to plug this number back into the file name b
+ut creating a new file called "name_0010" (originally it was "name_00
+09"). Here is the code I currently have, I know theres a more efficie
+nt way to do this...

$newfile = substr($newfile_n,0, 4);
$newfile =~ s/^(0)+//;
++$newfile;
print"$newfile\n";
$newfile = "000".$newfile; #if it gets to 100 then it will look like t
+his "0100"
substr($newfile, 1, 4);
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Re^3: adding 1 to a char of 1 by liverpole (Monsignor) on Jun 20, 2006 at 18:14 UTC
Not sure why you're using substr. Let me suggest that you keep the index and the basename separate. For example: `my $index = 0; for (my $i = 0; $i < 100; $i++) { $index++; my $fullname = sprintf "base_%04d", $index; printf "fullname = '%s'\n", $fullname; }` [download] will print 100 different names, starting with "name_0001" and ending with "name_0100". The %04d achieves this result; the "0" left-pads the integer value with zeroes, and the "4" gives you 4 decimal places. Read up on sprintf to get more details: perldoc -f sprintf. If you absolutely must get the last 4 digits of a string, you can use "substr" like this: `$last_4_chars = substr($my_string, -4);` [download] This has the effect of taking the "rest" of the string, starting at the 4th character from the end (since the offset -4 is negative) rather than from the beginning. s''(q.S:$/9=(T1';s;(..)(..);$..=substr+crypt($1,$2),2,3;eg;print$..$/	[reply] [d/l] [select]
Re^4: adding 1 to a char of 1 by Anonymous Monk on Jun 20, 2006 at 18:31 UTC
Great thats exactly what I was looking for.... Thanks to all u wisemen and women...	[reply]
Re^3: adding 1 to a char of 1 by ikegami (Patriarch) on Jun 20, 2006 at 20:47 UTC
Use substr to extract and replace: `my $oldfile = "name_0009"; my $num = substr($oldfile, -4); ++$num; my $newfile = substr($oldfile, 0, -4) . $num;` [download] Or use the lvalue form to simplify things: `my $oldfile = 'name_0009'; substr(my $newfile = $oldfile, -4)++;` [download]	[reply] [d/l] [select]