Pathologically Eclectic Rubbish Lister PerlMonks

### Re^4: How to split an integer??

by nithins (Sexton)
 on Dec 06, 2012 at 10:51 UTC ( #1007529=note: print w/replies, xml ) Need Help??

in reply to Re^3: How to split an integer??
in thread How to split an integer??

But my qn is i have a variable say \$a= 23 , now i need to add it as 2+3 which should give me ans 5 ... hw to do this ???

23 s stored as a single byte hence i cant split. But in words we can split character by character of a word in an array

```my @a = qw (data);
foreach \$aa(@a){
print \$aa."\n";
}

the above code will not work the sane for integers

Replies are listed 'Best First'.
Re^5: How to split an integer??
by tobyink (Abbot) on Dec 06, 2012 at 11:40 UTC

"23 s stored as a single byte hence i cant split."

Byte?! You're thinking in C terms! Go wash your mouth out with soap right now! ;-)

In Perl, strings and integers are both represented by the same data type - scalars. (Internally Perl represents scalars as a C struct which has separate string and integer slots. But you don't normally need to worry about such concerns.) If you have a variable that contains an integer value, such as 23, and pass it to something that expects a string, like split, that integer will be silently converted to a string.

Here's exactly the same function I posted before, only now I'm using the integer 23 as the input...

```use 5.010;
use strict;
use warnings;

# 23 is an integer.
#
say digit_sum(23);

# This expression is used to test that a string consists of a single
# digit. We use it a couple of different places, so we'll get define
# it once here.
#
use constant DIGIT => qr/^[0-9]\$/;

# This is the function which adds digits
#
sub digit_sum {
my \$string = shift;

# Otherwise, split into digits.
my @digits =
grep { \$_ =~ DIGIT }  # keep only the numeric characters
split '', \$string;    # split into characters

my \$sum = 0;
\$sum += \$_ for @digits;

# Handle the trivial case.
# If \$sum is just a single digit, return it as-is.
return \$sum if \$sum =~ DIGIT;

# Otherwise, recurse.
return digit_sum(\$sum);
}
perl -E'sub Monkey::do{say\$_,for@_,do{(\$monkey=[caller(0)]->[3])=~s{::}{ }and\$monkey}}"Monkey say"->Monkey::do'
Re^5: How to split an integer??
by McDarren (Abbot) on Dec 06, 2012 at 11:28 UTC
```my \$number = 23;
my @bits = split //, \$number;
my \$total;
for my \$bit (@bits) {
\$total += \$bit;
}

print "Number=\$number Total=\$total\n";
Re^5: How to split an integer??
by nvivek (Vicar) on Dec 07, 2012 at 04:44 UTC
For splitting integer value, need to specify pattern explicitly as null string as follows.
```# \$number contains numerical value which is greater than 9
split('', \$number);

Create A New User
Node Status?
node history
Node Type: note [id://1007529]
help
Chatterbox?
 [1nickt]: Hm, that is, how to prevent Perl from turning 1.0 into 1? I feel sure this must be an faq, but am reading perlnum and not finding the answer ... [Lady_Aleena]: 1nickt, why does it matter in this case? [1nickt]: Hm, perhaps this? "Operators which expect an integer force the argument into the integer format." [1nickt]: Can this be? So print [1nickt]: ... "expects an integer" ?

How do I use this? | Other CB clients
Other Users?
Others drinking their drinks and smoking their pipes about the Monastery: (12)
As of 2017-05-24 18:35 GMT
Sections?
Information?
Find Nodes?
Leftovers?
Voting Booth?
My favorite model of computation is ...

Results (186 votes). Check out past polls.