Hi, this is my first question post on PerlMonk. Just fyi, I have searched and tried for some good amount of time (>40min) and decided I could not find out what's wrong with my code. It's a simple one.

Basically, I am trying to convert negative number into specific length (10) binary. And it's simply refusing to do that. Here's the code:

my $neg = -1;
my $negBin = sprintf ("010.10b", $neg);
print $negBin; #returns a lot of 1s instead of 11_1111_1111. (without 
+underscores)

[download]

Another problem i had was if I am trying to convert 1024 into binary number: 

my $num = 1024;
my $bin = sprintf ("010.10b", $num);
print $bin; #returns 100_0000_0000 instead of 00_0000_0000

[download]

Apparently, there's something wrong with my sprintf formating....and I can't figure it out. I have used substr to simply cut the string to my desired length as a way around it but I am still interested to find out what I did wrong... I turn to the wisdom of PerlMonks out there. Thank you.

In reply to Converting negative number to binary with specific width by pjkang7

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