use Modern::Perl;
no warnings qw /uninitialized /;
my @result;

while (<DATA>) {
    chomp;
    my ($index, $value) = split /\t/;
    $result[$index] = $value;
}
$result[50] = 0 unless $result[50];

while (my ($index, $value) = each @result) {
    next if $index == 0;
    say "$index\t", $value+0;
}

__DATA__
33    5
34    7
36    7
37    8
38    0
[download]

1    0
2    0
3    0
4    0
5    0
6    0
7    0
(...)
31    0
32    0
33    5
34    7
35    0
36    7
37    8
38    0
39    0
(...)
49    0
50    0
[download]

Hi thank you for your response. I'm very new to this i tried to adapt it to make an input an output file but it is not working this is what i did, i put in # what i think is happeing and what i don't understand

#!/usr/bin/perl
use Modern::Perl;
no warnings qw /uninitialized /;
my @result; # assigns a list?

$INPUTFILE = "/Users/ts/numbers.txt"; # opens my file

open(INPUTFILE) or die("File error: input file\n");
open (OUTPUTFILE, "Users/ts/full_number.txt; #gives output file

while (<INPUTFILE>) {
    chomp; #removes new line
    my ($index, $value) = split /\t/; # a local list of varibles,not t
+o sure what the stuff after spilt is
    $result[$index] = $value; #?
}
$result[3000050] = 0 unless $result[3000050];

while (my ($index, $value) = each @result) {
    next if $index == 0;
    say "$index\t", $value+0;
   
    print (OUTPUTFILE $index\t, $value+0);
}


close (INPUTFILE);
close (OUTPUTFILE)
[download]

am i using the right version of perl for this

 his is perl 5, version 12, subversion 3 (v5.12.3) built for darwin-th
+read-multi-2level
(with 2 registered patches, see perl -V for more detail)
[download]

once again thank you for your patience!

Close but no cookie!

I have edited your code:

#!/usr/bin/perl
use Modern::Perl; #does an implict use strict; use warnings and activa
+tes "new" features
no warnings qw /uninitialized/;

my @result; # declares the array we will use to store the results

{ # starts a block
    open my $INPUTFILE, '<', '/Users/ts/numbers.txt' or die "File erro
+r: input file: $!";
    while (<$INPUTFILE>) {
        chomp; #removes new line
        my ($index, $value) = split /\t/; # splits each record at the 
+tab "\t" -character
        $result[$index] = $value; # and store the value in the array a
+t the right place
    }
} # ends the block, $INPUTFILE goes out of scope and closes the fileha
+ndle automatically

$result[3000050] = 0 unless $result[3000050];

{ # starts a block
    open my $OUTPUTFILE, '>', '/Users/ts/full_number.txt'or die "File 
+error: output file: $!";
    while (my ($index, $value) = each @result) {
        next if $index == 0;
        say $OUTPUTFILE, "$index\t", $value+0; # saves the results in 
+a >>indexnumber tab value<< format
    }
} # ends the block, $OUTPUTFILE goes out of scope and closes the fileh
+andle automatically
[download]

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

I'll make one big assumption: that your lines will be numbered in order. In other words, some may be missing, but line 34 will not come after line 35.

#!/usr/bin/perl
use Modern::Perl;

my $count =  1;         # track the next one to do
my $end   = 10;         # set to 3_000_050 for real run

open my $infile, '<', '937753-input.txt' or die $!;
while(<$infile>){
    if( /(\d+)\s+(\d+)/ ){           # extract two numbers
        my($k, $v) = ($1, $2);       # and put them in named variables
        if ( $k > $count ) {         # see if we skipped any
            for my $n ($count..($k-1)) {
                say "$n\t0";         # and ouput them with 0 if we did
            }
        }
        say "$k\t$v";             # then output the current one
        $count = $k + 1;          # and reset the counter
    }
}

if ( $count < $end ) {        # are any numbers missing at the end?
    for my $n ($count .. $end) {
        say "$n\t0";              # output them with zeros
    }
}
__END__

# 937753-input.txt
3   5
4   7
6   7
7   0
8   8

# tab-separated output
1       0
2       0
3       5
4       7
5       0
6       7
7       0
8       8
9       0
10      0
[download]

Hi yes i think your assumption is correct

I attempted your program but get an error message

 Can't locate Modern/Perl.pm in @INC (@INC contains: /Library/Perl/5.12/darwin-thread-multi-2level /Library/Perl/5.12 /Network/Library/Perl/5.12/darwin-thread-multi-2level /Network/Library/Perl/5.12 /Library/Perl/Updates/5.12.3 /System/Library/Perl/5.12/darwin-thread-multi-2level /System/Library/Perl/5.12 /System/Library/Perl/Extras/5.12/darwin-thread-multi-2level /System/Library/Perl/Extras/5.12 .) at ./aari.txt line 2.

i installed the latest version from the website am i meant to install something different?

 This is perl 5, version 12, subversion 3 (v5.12.3) built for darwin-t
+hread-multi-2level
(with 2 registered patches, see perl -V for more detail)

Copyright 1987-2010, Larry Wall
[download]

once again sorry about my dumbnes

EDIT aha i have installed modern perl

OK, now that's fixed, try this:

use Modern::Perl;
use autodie;

my $infile  = '/Users/ts/desktop/work/numbers.txt'; # Hmm...
my $outfile = 'Users/ts/full_number.txt';           # leading '/' or n
+ot?

open my $in, '<', $infile;

my @result;
while ( <$in> ) {
    my ( $index, $value ) = split;
    $result[$index] = $value;
}

close $in;

open my $out, '>', $outfile;
say $out "$_\t", $result[$_] || 0 for 1 .. 3_000_050;
close $out;
[download]

Sorry, I should have used the built-in stuff. Modern::Perl basically saves a few lines of typing by activating some things that are good practices for every program.

Aaron B.
My Woefully Neglected Blog, where I occasionally mention Perl.