%!PS

% begin included library code
% see https://codeberg.org/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 {
    /test.count test.count 1 add def
    {
        /test.pass test.pass 1 add def
    } {
        ( ) print
        test.count (....) cvs print
        (-fail) print
    } ifelse
} bind def

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


% end included library code

/longestparenthesis {
    0 dict begin
    /a exch def
    /ml 0 def
    0 1 a length 1 sub {
        /l exch def
        l 1 add 1 a length 1 sub {
            /r exch def
            /depth 0 def
            /valid true def
            l 1 r {
                /i exch def
                a i get 40 eq {
                    /depth depth 1 add def
                } {
                    /depth depth 1 sub def
                    depth 0 lt {
                        /valid false def
                        exit
                    } if
                } ifelse
            } for
            depth 0 ne {
                /valid false def
            } if
            valid {
                /ml ml r l sub 1 add max def
            } if
        } for
    } for
    ml
    end
} bind def

(longestparenthesis) test.start
(\(\(\)\(\)\)) longestparenthesis 6 eq test
(\)\(\)\(\)\)) longestparenthesis 4 eq test
(\(\(\(\)\)\)\(\)\(\(\(\(\)) longestparenthesis 8 eq test
(\)\)\)\)\(\(\(\)\() longestparenthesis 2 eq test
(\(\)\(\(\)) longestparenthesis 2 eq test
test.end