This is XeTeX, Version 3.14159265-2.6-0.99996 (MiKTeX 2.9 64-bit) (preloaded format=xetex 2018.9.10)  5 OCT 2018 12:27
entering extended mode
**./5_5.tex
(5_5.tex
Underfull \vbox (badness 10000) has occurred while \output is active
\vbox(413.54437+3.44841)x293.09511
.\glue(\topskip) 3.05556
.\hbox(6.94444+1.94444)x293.09511, glue set - 0.29471
..\hbox(0.0+0.0)x0.0
..\tenbf 5
..\tenbf .
..\tenbf 5
..\glue 3.83331 plus 1.91666 minus 1.27777
..etc.
.\glue -5.0
.\glue(\parskip) 10.0
.\glue(\baselineskip) 2.55556
.etc.

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Output written on 5_5.pdf (2 pages).