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<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>Hi,
all<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>I
wrote function that delete elements from list by indexes:<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>delIndexes::[Int]-&gt;[a]-&gt;[a</span></font><span
dir=RTL></span><font size=2 face=Arial><span lang=HE dir=RTL style='font-size:
10.0pt;font-family:Arial'><span dir=RTL></span>]<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>delIndexes
[] list = list</span></font><font size=2 face=Arial><span lang=HE dir=RTL
style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>delIndexes</span></font><span
dir=RTL></span><font size=2 face=Arial><span lang=HE dir=RTL style='font-size:
10.0pt;font-family:Arial'><span dir=RTL></span> _ [] = []<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>delIndexes
indexes list = take x list&nbsp; ++ delIndexes ( map (\y-&gt;y-x-1) xs ) ( drop
(x+1) list</span></font><span dir=RTL></span><font size=2 face=Arial><span
lang=HE dir=RTL style='font-size:10.0pt;font-family:Arial'><span dir=RTL></span>(<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span lang=HE dir=RTL style='font-size:10.0pt;
font-family:Arial'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>where</span></font><font
size=2 face=Arial><span lang=HE dir=RTL style='font-size:10.0pt;font-family:
Arial'><o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span lang=HE dir=RTL style='font-size:10.0pt;
font-family:Arial'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; )</span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>x:xs)=sort
indexes<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>There
is problem that in each step of recursion this function sort list of indexes (
in last line)<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>How
can I write this code that sorting will be executed only once (in first step)?<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>Thank
you, Nadav<o:p></o:p></span></font></p>

<p class=MsoNormal dir=LTR style='text-align:left;direction:ltr;unicode-bidi:
embed'><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

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