Re^2: Unexpected output for given program with write function

Thanks, I am newbie to perl and there tricks will surely helped me. is " $hashref2 = $VAR2->$k " deprecated ? I tried to use this, but shows the warning with same, Can i use

         if ( $file_no1 eq 0 )
                if ( $mkey eq $k )
                    if ($k eq $file_no1-1 )
            if ( $count1 eq $count2 )
    if ( $flag eq 1 )
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        if ( $file_no1 == 0 )
                if ( $mkey == $k )
                    if ($k == $file_no1-1 )
            if ( $count1 == $count2 )
    if ( $flag == 1 )
[download]

? and how do i compare string if i want to, Thanks, Dipesh

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Re^3: Unexpected output for given program with write function by jwkrahn (Abbot) on Jun 10, 2011 at 18:24 UTC
No `$hashref2 = $VAR2->[$k];` is not deprecated, and what warning did you get? Perl uses different operators for comparing numbers or strings. See perlop for details. Also, I was thinking about this code in your program: `push @array, $k; # Sort the array now because we pushed the value in ar +ray. my $srt; for (my $s=0;$s<@array; $s++) { for (my $r=0;$r<@array;$r++) { if ($s ne $r) { if($array[$s]<$array[$r]) { $srt=$array[$s]; $array[$s]=$array[$r]; $array[$r]=$srt; } } } }` [download] You are adding one element to an array and then sorting the whole array using an algorithm that is O( N² ). And even if you switched to Perl's built-in sort function: `@array = sort { $a <=> $b } @array, $k;` [download] that would at best be O( log N ). However, you don't really need to sort the array, just insert `$k` in the correct place which would give you an O( N ) algorithm: `my $index = 0; ++$index while $k >= $array[ $index ]; splice @array, $index, 0, $k;` [download]	[reply] [d/l] [select]

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Re^3: Unexpected output for given program with write function
by jwkrahn (Abbot) on Jun 10, 2011 at 18:24 UTC

No $hashref2 = $VAR2->[$k]; is not deprecated, and what warning did you get?

Perl uses different operators for comparing numbers or strings. See perlop for details.

Also, I was thinking about this code in your program:

push @array, $k; # Sort the array now because we pushed the value in ar +ray. my $srt; for (my $s=0;$s<@array; $s++) { for (my $r=0;$r<@array;$r++) { if ($s ne $r) { if($array[$s]<$array[$r]) { $srt=$array[$s]; $array[$s]=$array[$r]; $array[$r]=$srt; } } } }
[download]

You are adding one element to an array and then sorting the whole array using an algorithm that is O( N² ). And even if you switched to Perl's built-in sort function:

@array = sort { $a <=> $b } @array, $k;
[download]

$k

my $index = 0;
++$index while $k >= $array[ $index ];
splice @array, $index, 0, $k;
[download]

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