%!PS

% begin included library code
% see https://github.com/Firedrake/postscript-libraries/
/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

/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


% end included library code

/divisiblepairs {
    4 dict begin
    /k exch def
    /a exch def
    0
    0
    1
    a length 2 sub {
        /ai exch def
        ai 1 add
        1
        a length 1 sub {
            /bi exch def
            a ai get a bi get add k mod 0 eq {
                1 add
            } if
        } for
    } for
    end
} bind def

(divisiblepairs) test.start
[ 4 5 1 6 ] 2 divisiblepairs 2 eq test
[ 1 2 3 4 ] 2 divisiblepairs 2 eq test
[ 1 3 4 5 ] 3 divisiblepairs 2 eq test
[ 5 1 2 3 ] 4 divisiblepairs 2 eq test
[ 7 2 4 5 ] 4 divisiblepairs 1 eq test
test.end