%! Not DSC compliant

/ib {
    exch
    1 exch 1 sub bitshift
    xor
} def

/str 50 string def
/fs 12 def
/Helvetica findfont
fs scalefont setfont
20 750 translate
/line 0 def
/testnum 1 def

/disptest {
    0 line moveto testnum str cvs show (.) show
    dup
    50 line moveto str cvs show
    exch
    dup
    100 line moveto str cvs show
    exch
    ib
    dup
    150 line moveto str cvs show
    eq { (Pass) } { (FAIL) } ifelse
    200 line moveto show
    /line line fs 2 mul sub def
    /testnum testnum 1 add def
} def

8 3 12 disptest
26 4 18 disptest

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