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Sample perl programs

1.biggest of two numbers
print "Enter two numbers\n";
$a = <STDIN> ;
$b = <STDIN> ;

if($a>$b)
{$big=$a;}
else
{$big=$b;}

print "biggest=$big";
2.Biggest of 3 numbers
print "Enter three numbers\n";
$a = <STDIN> ;
$b = <STDIN> ;
$c = <STDIN> ;
if ($a >$b and $a > $c)
 {print "biggest is=",$a;}
elsif ($b >$a and $b > $c)
 {print "biggest is=",$b;}
else
 {print  "biggest is=",$c;}
3.printing 1-100 ( for and while)
#print 1-100

for($i=1;$i<=100;$i++)
{
print "$i\n";
}
$i=1
while($i<=100)
{
print "$i\n";
$i=$i+1;
}

4. Creating a 10 elemnt array and sorting it in ascending and descending order
# @a   IS THE ARRAY
print "enter 10 numbers\n";
for($i=0;$i<10;$i++)
{
$x=<STDIN>;
push(@a,$x);
}
@aso=sort { $a <=> $b } @a;
@dso=sort { $b <=> $a } @a;
print "Array is ascending order \n";
print "@aso";
print "Array in descending order \n";
print "@dso";

5.Reading list of 10 names and sorting it

print "enter 10 names\n";
for($i=0;$i<10;$i++)
{
$x=<STDIN>;
push(@a,$x);
}
@aso=sort  @a;
@dso=reverse sort  @a;
print "Names in sorted order \n";
print "@aso";
print "Names in reverse order \n";
print "@dso";


6.Read 5 numbers and find the sum and average
# @a IS THE ARRAY
print "enter 5 numbers\n";

for($i=0;$i<5;$i++)
{
$x=<STDIN>;
push(@a,$x);
}

foreach $x (@a)
{
 $s=$s+$x;
}
$n=@a;
$avg=$s/$n;

print "sum=$s Average= $avg\n";


7. Display all the files in /tmp directory.

$dir = "/tmp/*";
@files = glob( $dir );

foreach (@files )
{
   print $_ . "\n";
}

8.opening a file stud and displaying its contents
open(DATA, "<stud") ;

while(<DATA>)
{
  
  print $_;
}

9.opening a file stud and displaying  rno name only.
open(DATA, "<stud") ;

while(<DATA>)
{
  @a=split('\Q|',$_); # split each line and store it into an array a.
  print "$a[0]   $a[1]\n";
}
10.Read and string and remove all the occurrence of the word 'is'.
print "Enter the string\n";
$str=<STDIN>;
@words=split(' ',$str);
$nw=@words;
print "Number of words=$nw\n";
$ns="";
foreach $w  (@words)  # will take each word from the words array
{
if( $w ne "is")
{
$ns=$ns." ".$w; #creating a new string after removing word is
}
}
print "New String After Removing is.\n";
print "$ns\n";
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