%!PS

/aeq {
    2 dict begin
    /a exch def
    /b exch def
    a length b length eq {
        /e true def
        0 1 a length 1 sub {
            dup a exch get
            exch b exch get ne {
                /e false def
                exit
            } if
        } for
        e
    } {
        false
    } ifelse
    end
} bind def

/apush { % [a b] c -> [a b c]
    /t exch def
    [ exch aload pop t ]
} bind def

/i2s {
    dup 0 le {
        (0)
    } {
        dup log cvi 1 add string cvs
    } ifelse
} bind def

/fds {
    /n exch def
    /ft n 4 mul dict def
    /out 0 array def
    /f [ 0 1 ] def
    f {
        ft exch true put
    } forall
    /k 0 def
    {
        /ds 0 def
        /j k def
        {
            j 0 gt {
                /ds ds j 10 mod add def
                /j j 10 idiv def
            } {
                exit
            } ifelse
        } loop
        {
            f 0 get ds gt {
                exit
            } if
            f 0 get f 1 get add
            f 1 get f exch 0 exch put
            f exch 1 exch put
            ft f 0 get true put
        } loop
        ft ds known {
            /out out k apush def
            out length n ge {
                exit
            } if
        } if
        /k k 1 add def
    } loop
    out
} bind def

8 fds [0 1 2 3 5 8 10 11 ] aeq { (Pass) } { (FAIL) } ifelse print ( ) print

20 fds [ 0 1 2 3 5 8 10 11 12 14 17 20 21 23 26 30 32 35 41 44] aeq { (Pass) } { (FAIL) } ifelse print ( ) print

61 fds [0 1 2 3 5 8 10 11 12 14 17 20 21 23 26 30 32 35 41 44 49 50 53 58 62 67 71 76 80 85 94 100 101 102 104 107 110 111 113 116 120 122 125 131 134 139 140 143 148 152 157 161 166 170 175 184 193 200 201 203 206 ] aeq { (Pass) } { (FAIL) } ifelse =