in reply to decimal to binary conversion

Hi there

please try this version of your code, it worked for me ^_^

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

print "Enter decimal number less than 256:"; 
my $decimal; 
$decimal=<STDIN>; 
chomp $decimal; 
# $decimal += 0;
print (($decimal & 0x80) <=> 0); 
print (($decimal & 0x40) <=> 0); 
print (($decimal & 0x20) <=> 0); 
print (($decimal & 0x10) <=> 0); 
print (($decimal & 0x08) <=> 0); 
print (($decimal & 0x04) <=> 0); 
print (($decimal & 0x02) <=> 0); 
print (($decimal & 0x01) <=> 0);

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Re^2: decimal to binary conversion
by AnomalousMonk (Archbishop) on Jun 05, 2015 at 01:14 UTC

    What is the reason for the n <=> 0 comparison?

    Give a man a fish:  <%-(-(-(-<

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[d/l]
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      The usage for <=> here in the masking expreasion ($decimal & 0x80) is to test if this 8th bit is zero or one, also you can do it like:

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

print "Enter decimal number less than 256:"; 
my $decimal; 
$decimal=<STDIN>; 
chomp $decimal; 
# $decimal += 0;
print (($decimal & 0x80)? (1) : (0) );    # to test the 8th bit
print (($decimal & 0x40)? (1) : (0) );    # to test the 7th bit
print (($decimal & 0x20)? (1) : (0) );    # to test the 6th bit
print (($decimal & 0x10)? (1) : (0) );    # to test the 5th bit
print (($decimal & 0x08)? (1) : (0) );    # to test the 4th bit
print (($decimal & 0x04)? (1) : (0) );    # to test the 3th bit
print (($decimal & 0x02)? (1) : (0) );    # to test the 2nd bit
print (($decimal & 0x01)? (1) : (0) );    # to test the 1st bit

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[d/l]
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        Are so many parentheses needed with the lower precedence  ? : Conditional Operator? Also, rather than using what looks like an unrolled loop for printing bits, is there any way to use a while- or for-loop here?

        Give a man a fish:  <%-(-(-(-<

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