my $i=1;
$i=~/(.)/;
while ($i++<=4) {
    print "\$i = $i\n";
    print "first:  \$1 = $1\n";
    $i=~/(3)/;
    print "second: \$1 = $1\n";
}
print "after: \$1 = $1\n";

##</code><code>##

$i = 2
first:  $1 = 1
second: $1 = 1
$i = 3
first:  $1 = 1
second: $1 = 3
$i = 4
first:  $1 = 3
second: $1 = 3
after: $1 = 1