@foo = ( 1 , 3 , 5 , 7 );
@bar = ( 2 , 4 , 6 , 8 , 9);
print STDOUT my @foobar = map { ( $_, shift @foo ) } @bar;

##</code><code>##

@foo = ( 2 , 4 , 6 , 8 );
@bar = ( 1 , 3 , 5 , 7, 9);
$len = @foo;
print STDOUT my @foobar = (
        (map { ( $_, shift @foo ) } @bar[0 .. $len - 1]),
        @bar[$len .. $#bar]  );