Re: Unexpected output for given program with write function

if ( $file_no1 gt $file_no2 )
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You are using text comparison on numbers which will not work correctly:

$ perl -le'print "$ARGV[0] is ", $ARGV[0] gt $ARGV[1] ? "" : "NOT ", "
+greater than $ARGV[1]"'  12 18
12 is NOT greater than 18
$ perl -le'print "$ARGV[0] is ", $ARGV[0] gt $ARGV[1] ? "" : "NOT ", "
+greater than $ARGV[1]"'  12 10
12 is greater than 10
$ perl -le'print "$ARGV[0] is ", $ARGV[0] gt $ARGV[1] ? "" : "NOT ", "
+greater than $ARGV[1]"'  7 10
7 is greater than 10
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Also wrong on these lines:

if ( $file_no1 eq 0 ) if ( $mkey eq $k ) if ($k eq $file_no1-1 ) if ( $count1 eq $count2 ) if ( $flag eq 1 )
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$indexed= "$"; foreach my $index (@array) { $temp=$index+0; $indexed="$indexed $temp"; $indexed="$indexed,"; } $indexed ="$indexed $";
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Or just:

            $indexed = "(" . join ", ", @array, ")";
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$hashref2 = @$VAR2[$k];
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That is correctly written as:

            $hashref2 = $VAR2->[$k];
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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; } } } }
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That is usually written as:

                for my $s ( 0 .. $#array )
                {
                    for my $r ( 0 .. $#array )
                    {
                        if ( $s != $r && $array[ $s ] < $array[ $r ] )
                        {
                            @array[ $r, $s ] = @array[ $s, $r ];
                        }
                    }
                }
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Or as:

                @array = sort { $a <=> $b } @array;
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Comment on Re: Unexpected output for given program with write function Select or Download Code

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Re^2: Unexpected output for given program with write function by dipesh777 (Novice) on Jun 10, 2011 at 14:52 UTC
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 )` [download] as `if ( $file_no1 == 0 ) if ( $mkey == $k ) if ($k == $file_no1-1 ) if ( $count1 == $count2 ) if ( $flag == 1 )` [download] ? and how do i compare string if i want to, Thanks, Dipesh	[reply] [d/l] [select]
Re^3: Unexpected output for given program with write function by jwkrahn (Abbot) on Jun 10, 2011 at 18:24 UTC
No `$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]