The following pseudocode represents an algorithm intended to output the last three lines as they appear in a text file. Line numbers are provided for reference only.
```pseudocode
10 PROCEDURE LastLines(ThisFile : STRING)
11 DECLARE ThisLine : STRING
12 DECLARE Buffer : ARRAY[1:3] OF STRING
13 DECLARE LineNum : INTEGER
14 LineNum ← 1
15 OPENFILE ThisFile FOR READ
16
17 WHILE NOT EOF(ThisFile)
18 READFILE Thisfile, ThisLine // read a line
19 Buffer[LineNum] ← ThisLine
20 LineNum ← LineNum + 1
21 IF LineNum = 4 THEN
22 LineNum ← 1
23 ENDIF
24 ENDWHILE
25
26 CLOSEFILE ThisFile
27 FOR LineNum ← 1 TO 3
28 OUTPUT Buffer[LineNum]
29 NEXT LineNum
30 ENDPROCEDURE
```

Question

The following pseudocode represents an algorithm intended to output the last three lines as they appear in a text file. Line numbers are provided for reference only.
```pseudocode
10 PROCEDURE LastLines(ThisFile : STRING)
11     DECLARE ThisLine : STRING
12     DECLARE Buffer : ARRAY[1:3] OF STRING
13     DECLARE LineNum : INTEGER
14     LineNum ← 1
15     OPENFILE ThisFile FOR READ
16 
17     WHILE NOT EOF(ThisFile)
18         READFILE Thisfile, ThisLine // read a line
19         Buffer[LineNum] ← ThisLine
20         LineNum ← LineNum + 1
21         IF LineNum = 4 THEN
22             LineNum ← 1
23         ENDIF
24     ENDWHILE
25 
26     CLOSEFILE ThisFile
27     FOR LineNum ← 1 TO 3
28         OUTPUT Buffer[LineNum]
29     NEXT LineNum
30 ENDPROCEDURE
```

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