%!PS

% begin included library code
% see https://github.com/Firedrake/postscript-libraries/
/genprimes {
    6 dict begin
    /mx exch def
    /primesh mx dict def
    2 1 3 {
        dup mx le {
            primesh exch true put
        } {
            pop
        } ifelse
    } for
    6 6 mx 1 add {
        dup 1 sub exch 1 add 2 exch {
            dup mx le {
                primesh exch true put
            } {
                pop
            } ifelse
        } for
    } for
    /q [ 3 5 7 ] def
    /qi 0 def
    /p 2 def
    /mr mx sqrt cvi def
    {
        p mr le not {
            exit
        } if
        primesh p known {
            p dup mul p mx {
                primesh exch undef
            } for
        } if
        q length qi sub 2 le {
            /q q q q length 1 sub get 4 add apush def
            /q q q q length 1 sub get 2 add apush def
        } if
        /p q qi get def
        /qi qi 1 add def
    } loop
    primesh keys
    end
} bind def

/apush.right { % [a b] c -> [a b c]
    exch
    [ exch aload length 2 add -1 roll ]
} bind def

/apush { apush.right } bind def

/keys { % dict -> array of dict keys
    [ exch
      {
          pop
      } forall
    ]
} bind def

/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

/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

/primecount {
    1 sub genprimes length
} bind def

(primecount) test.start
10 primecount 4 eq test
15 primecount 6 eq test
1 primecount 0 eq test
25 primecount 9 eq test
test.end