%!PS

% begin included library code
% see https://github.com/Firedrake/postscript-libraries/
/test.end {
    ( ) print
    test.count 0 gt {
        (Passed ) print
        test.pass (...) cvs print
        (/) print
        test.count (...) cvs print
        ( \() print
        test.pass 100 mul test.count idiv (...) cvs print
        (%\)) print
        (\r\n) print
    } if
} bind def

/test.start {
    print (:) print
    /test.pass 0 def
    /test.count 0 def
} bind def

/toset { % array -> dict of (value, true)
    << exch
       {
           true
       } forall
    >>
} bind def

/test {
    /test.count test.count 1 add def
    {
        /test.pass test.pass 1 add def
    } {
        ( ) print
        test.count (....) cvs print
        (-fail) print
    } ifelse
} bind def


% end included library code

/missingnumber {
    3 dict begin
    /l exch def
    /v l toset def
    0
    0 1 l length {
        /i exch def
        v i known not {
            pop i
        } if
    } for
    end
} bind def

(missingnumber) test.start
[0 1 3] missingnumber 2 eq test
[0 1] missingnumber 2 eq test
test.end