Another way to do it:

$ perl -le'
my @a = qw( 1 9 3 4 5 6 7 2 4 3 );
my @b = qw( x y z z a z z z b c );
my $char = "z";

my @anew;
for my $i ( 0 .. $#b ) {
    if ( $b[ $i ] =~ ?^$char$? ) {
        push @anew, $a[ $i ];
        }
    elsif ( $b[ $i ] =~ /^$char$/ ) {
        next;
        }
    else {
        push @anew, $a[ $i ];
        reset;
        }
    }
              
print "@anew";
'
1 9 3 5 6 4 3
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