Re: join two binary numbers

hara wrote:
My idea is to make a binary number into a 6 digit number.
From a calculation i may get a 2/3/4 digit number and i want to convert
it to 6 digit number by adding zeros on the left of that number.

Finally you tell us what you really want: it is an output formatting problem. Nothing to do with or'ing binary numbers. Do you really imagine that Perl is somehow storing binary numbers of sub-byte size?

You are still ignoring the posting guidelines for this group though. Many here will be running out of patience. Quote context. Post complete scripts.

Suppose i got
$a="1101";
To make it 6 digit i tried doing it like
$res="000000" | $a;
But i am getting 110100

As you have been told many times already, that is because "1101" is a *string* of four characters, and "000000" is a *string* of six characters. They are not binary numbers.

Let's consider your example. Complete script:

----

#!/usr/bin/perl
use strict;
use warnings;

my $num = '1101';
my $res = '000000' | $num;
print $res;

----

Output: 110100

What is happening here? Perl is doing an bitwise or of each *byte* of the two strings, padding $num of the right with two zero bytes to match the length of $res.

Perhaps this will convince you. The ASCII code for '3' is 0b00110011. For '4' it is 0b00110100. For '7' it is 0b00110111. So, a bitwise or of '3' and '4' will give '7'. Let's see:

----

#!/usr/bin/perl
use strict;
use warnings;

my $num = '1103';
my $res = '000400' | $num;
print $res;

----

Output: 110700

Likewise '1103' | '000a00' results in '110s00', since the ASCII codes are '3': 0b00110011, 'a': 0b01100001, 's': 0b01110011.


But i want 001101
Is it possible to do that?

See the many solutions already posted here.

DS
.

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