# File reg3.pl
# Regular expressions. Substitute s. String =~ s/OLD/NEW/

$seq = 'mel a 1 45 nie';
print "Sequence is ", $seq;

$seq =~ s/[0-9]//g; 
print "\nDelete all(g) digits: ", $seq;  # mel a   nie;

$seq =~ s/\s//g; 
print "\nDelete all(g) spaces: ", $seq;	# melanie

$seq =~ s/[\s0-9]//g;
print "\nDelete all(g) both spaces and numbers: ",$seq; # melanie

$seq =~ s/E//i;
print "\nDELETE FIRST e any case(i): ",$seq; # mlanie

$seq =~ s/m/M/;
print "\nSubstitute first m with upper case M: ",$seq; # Mlanie

$seq =~ s/M/XXX/;
print "\nSubstitute first M with XXX: ",$seq; # XXXlanie

$seq =~ s/XXX/Me/;
print "\nSubstitute first XXX with Me: ",$seq; # Melanie
exit