$x = hypotenuse($y,4);
# $x now contains 5
print $x."\n";

$x = hypotenuse((3*$y),12);
# $x now contains 15  
print $x."\n";
 
$value_e = E();
print $value_e."\n";
# $value_e now contains 2.71828182845905
  

#########
  
sub hypotenuse {
    my ($a,$b) = @_;
    return sqrt($a**2 + $b**2);
}
  
sub E {
    return 2.71828182845905;
}