Hello fellow Monks!
I am trying to optimize a code that I have, which is supposed to do the following:
If you have 2 strings, like the following:
$str_no_dash='
IIIIIIIIIIIIIIIIIIIIIIIIIIIMMMMMMMOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOMMMMMM
+MMMIIIMMMMMMMMMMMOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOMMMMMMMMMI
+IIMMMMMMMMMOOOOMMMMMMMMMIIMMMMMMMMMOOOOOOOOOOOOOOOOOMMMMMMMMMIIIIMMMM
+MMMMMOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOMMMMMMMIIIIIMMM
+MMMMMMMMOOOOOOOOOOOOOOOOOOOMMMMMMMMMMMIIIIIMMMMMMMMMMMOOOOOOOOOOOO';
$str_with_dash='VNRV-L-K--R-------PL------A-------N---------PV----N---
+--D----V--G---V--T-----L-----G------T--------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+---RG----E--R----RG--E-F-----D-L--G----WN----A----N-------D----------
+----------A-------AR-----F---RM----T----G-----A-----A--E-N----S-N-SF-
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+-----------------------------------------------R---------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+------------------------------------DQF--Q-----L-N-R-Q---A----IA--P--
+S----------------AQ--F---------K-------L----D---R----------D--------T
+--V--L--------N--V-------E--FDY-LHD----------------------------------
+---------------------------------------------------------------------
+------------------------------------------------------R--R---T--S---D
+--Q--GI-------------------------------------P--AYR-------------------
+------------------GRPV---------------DVP-IN----TY-Y-GSAD-------------
+----------------------------------------------------------------GVNSS
+YNDV-S----A-K--SA-----------------T-V--------S----L-------------D----
+-H-----R---------------F----N-----------D-S-L-S-F------------------HG
+--A------------------------------------------------------------------
+-------------------------------------------I--R--AY------------------
+--------DF--SL------ER-----------------------------------------------
+-----K-N---Y-V-----T----Y----E--P-I---K-TA---------------------------
+---------------------------------------------------------------------
+-----------------------------------------------AHP--------------VV--T
+--L--D-Q--S--T-------------------------------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+RQRTDH-----G--I-D---G--L--F--EL----------------------------------T---
+-QK---TS-----------LFGM----------------------------------------------
+--------------------------RH--E----------L---L--------Y------G--L----
+---E--LS--Q----Q--Q-K------------------------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+---------------------F--DTIY--------S---------------V-S--------------
+---------------------------------------------------------------K---VA
+-TYDLFNP----------------------------------QPVVLPG--VP----------TGT---
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+----------RA----K-----------------------TNASTVVG-LA-----G--V-Y----A--
+------Q-------D--L--IS-----------------------L---------T---E--H------
+-------W---K-----V---L--A---G----------------------------L-----------
+--R---F-------------------------------------DY---------------------L-
+-------------------------------NQ-------------I----------------------
+RHDYTSSNV------------------------------------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+---------------------------------------------------------------------
+--------------------------NLDRTDHAW----SP-------R---V----------------
+-------------------G--LI------Y-------------------------------E--P---
+----L---DW----------------------------------L--TL--Y----G--SFSQ------
+-----S-F------S-------------------------------------P-L--A-----------
+--D----T----L-------I-S--SG------------A-----------------------------
+---------------------------------------------------------------';

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to create a new string, which will have the same letters as $str_no_dash, but with - in the same positions as $str_with_dash.
The thing is that I can do it with split but I think there could be a faster solution using for loop...Can you show me how?
@final=();
@split_str_no_dash = split(//, $str_no_dash);
@split_str_with_dash = split(//, $str_with_dash);

$count_pos = -1;
$count_pred = -1;

@str_final=();            
foreach $b(@split_str_with_dash)
{
    if ($b=~/\./ or $b=~/-/)
    {
        $count_pos++;
        $str_final[$count_pos]=$b;
    }
    elsif ($b!~/\./ && $b!~/-/)     
    {            
        $count_pos++;
        $count_pred++;
        $str_final[$count_pos]=$split_str_no_dash[$count_pred];
        }
    }                        

    $final_string=join("", @str_final);
}

[download]

In reply to How can I do this action WITHOUT split? by Anonymous Monk

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