%!PS

% begin included library code
% see https://github.com/Firedrake/postscript-libraries/
/quicksort { % [ a c b ] -> [ a b c ]
    1 dict begin
    /arr exch def
    0 arr length 1 sub quicksort.main
    arr
    end
} bind def

/quicksort.partition {
    3 dict begin
    /pivot arr hi lo add 2 idiv get def
    /i lo 1 sub def
    /j hi 1 add def
    {
        {
            /i i 1 add def
            arr i get pivot ge {
                exit
            } if
        } loop
        {
            /j j 1 sub def
            arr j get pivot le {
                exit
            } if
        } loop
        i j ge {
            j
            exit
        } if
        i j quicksort.swap
    } loop
    end
} bind def

/quicksort.main { % lo hi -> (null)
    3 dict begin
    /hi exch def
    /lo exch def
    /xit false def
    lo 0 lt {
        /xit true def
    } if
    hi 0 lt {
        /xit true def
    } if
    lo hi ge {
        /xit true def
    } if
    xit not {
        /p quicksort.partition def
        lo p quicksort.main
        p 1 add hi quicksort.main
    } if
    end
} bind def

/quicksort.swap {
    2 dict begin
    /bi exch def
    /ai exch def
    arr ai get
    arr bi get
    arr exch ai exch put
    arr exch bi exch put
    end
} 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

/ymd2jd {
    4 dict begin
    aload pop
    /d exch def
    /m exch def
    /y exch def
    /mn m 14 sub 12 idiv def
    y 4800 add mn add 1461 mul 4 idiv
    mn 12 mul neg 2 sub m add 367 mul 12 idiv add
    y 4900 add mn add 100 idiv 3 mul 4 idiv sub
    d add
    32075 sub
    end
} 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

/daystogether {
    2 dict begin
    /starts 2 array def
    /ends 2 array def
    dup 0 get s2jd starts exch 1 exch put
    1 get s2jd ends exch 1 exch put
    dup 0 get s2jd starts exch 0 exch put
    1 get s2jd ends exch 0 exch put
    starts quicksort
    ends quicksort
    ends 0 get starts 1 get ge {
        ends 0 get starts 1 get sub 1 add
    } {
        0
    } ifelse
    end
} bind def

/s2jd {
    [ exch
      2022 exch
      dup
      3 2 getinterval cvi exch
      0 2 getinterval cvi
    ]
    ymd2jd
} bind def

(daystogether) test.start
[ (12-01) (20-01) ] [ (15-01) (18-01) ] daystogether 4 eq test
[ (02-03) (12-03) ] [ (13-03) (14-03) ] daystogether 0 eq test
[ (02-03) (12-03) ] [ (11-03) (15-03) ] daystogether 2 eq test
[ (30-03) (05-04) ] [ (28-03) (02-04) ] daystogether 4 eq test
test.end