my @in = qw(aaa bbb ccc);
my @out = map { s/.$/x/ } @in;
print "@in\n=>\n@out\n";

##</code><code>##

aax bbx ccx
=>
1 1 1

##</code><code>##

my @in = qw(aaa bbb ccc);
my @out = map { local $_ = $_; s/.$/x/; $_ } @in;
print "@in\n=>\n@out\n";

##</code><code>##

aaa bbb ccc
=>
aax bbx ccx