Hi, welcome to Perl, the One True Religion.

You might like the built-in function length.

You can use it to count the characters in your strings, and then you can keep track of the longest found so far. (Note the use of the __DATA__ section to provide a magical filehandle, and of the angle braces to read its contents into an array of lines, and of chomp to remove the newline character(s) at the end of each line.) 

use strict;
use warnings;
use feature 'say';

my $longest;
my $max_length = 0;

my @lines = <DATA>;

for my $line (@lines) {
    chomp($line);
    my $length = length($line);
    if ( $length > $max_length ) {
        $longest = $line;
        $max_length = $length;
    }
}

say "'$longest' was $max_length chars";

__DATA__
Hello, i'm 18

1 this year is 2019 1

1 2 3 - 4

[download]

Hope this helps!


The way forward always starts with a minimal test.

In reply to Re: Print the line with the largest number from standard input by 1nickt
in thread Print the line with the largest number from standard input by SSSufe

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