sub benchmark_routine
{
    my ($testFn, $testName)=@_;

    foreach(@testCases) {
        my ($sentence, $wantedLetters, $expectedResult) = @$_;
		$testFn->($sentence, $wantedLetters) for (1..20);
        die "$testName test failed ($sentence, $wantedLetters)"
          unless (($testFn->($sentence, $wantedLetters))==$expectedResult);
    }
}

##</code><code>##

sub RMGir_indexNot {
    my ($sentence, $wantedLetters)=@_;

    # don't need this variable (or any of them, in
    # fact -- they're just here for clarity.
    # we could work straight out of @_ if we wanted
    # this terser
    # Also, the $[ check is just pedantic - if someone
    # changes $[, shoot them.
    return !(grep index($sentence,$_)<$[,
                                  split //,$wantedLetters);
}