use strict;
use warnings;

print "map\t";
1 =~ /1/; 
map {
    print "$& ";
    2 =~ /2/; 
    print "$& ";
} 0, 1;
print "$&\n";

print "block\t";
my $n = 1;
1 =~ /1/; 
{
    print "$& ";
    2 =~ /2/; 
    print "$& ";
    redo if $n --
};
print "$&\n";

print "foreach\t";
1 =~ /1/; 
for (0, 1) {
    print "$& ";
    2 =~ /2/; 
    print "$& ";
}
print "$&\n";

print "while\t";
my $m = 2;
1 =~ /1/; 
while ($m --) {
    print "$& ";
    2 =~ /2/; 
    print "$& ";
};
print "$&\n";

print "for\t";
1 =~ /1/; 
for (my $i = 0; $i <= 1; $i++) {
    print "$& ";
    2 =~ /2/; 
    print "$& ";
}
print "$&\n";

__END__

map     1 2 1 2 1
block   1 2 1 2 1
foreach 1 2 2 2 1
while   1 2 2 2 1
for     1 2 1 2 1