10 <Frogram to list lines of a file ir: reverse order.
20 Snows use of pointers, records, MARK and RELEASE.Ž

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30
40 FROGRAM Reverseline; -
50
60 TYFE elem<RECORD : CCreste linred-list structure:
70 next! "elemn;
80 ch? CHAR
99 END;
100 links"elem;
110:
120 VAR prev,cursheapi? link; <all pointers to 'elen"?
130
140 EEGIN
150 KREFEAT čdo this mars timesž
160 MARK (heap); ; tassign top of heap to «m 1p'
) 179 prevtzNIL; <points to no varaible ye..: zi
180 MHILE NOT EOLN DO
199 EEGIN
206 NEH(cur); Cereate a new dynamic reco:cd: |
240 READ(cur?.,cn); čand assign its field toioja
se li cnaracter from fitke.ž i
230 cur4,nentiaprev; Kthis faeld's pointer adretjes: |
240 previncur Zprevidws record.ž
podj, END: '
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270 £Hrite ovt the line bsekwards by scannins the records
2€0 set up backuards.>
299
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320 EEGIN
z30 MRITE(cur".ch); DnRz Eh bhlio taaid. i.e. S stala
36 curiscevr",.next ' £a odre-s oreviovs filealt.)

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