In Secondary Education Examination of Nepal altogether 15 marks of weightage is carried by QBASIC portion only, Out of which 2 marks question regarding debugging is always asked. Student will be given with program having syntactical error and are requested to debug the given program. In this question students have to search for the wrong syntax normally called bug and eliminate it with the correct syntax. Following are some of the frequently repeated debugging questions with solution.

Rewrite the given program after correcting the bugs.

Q1)

REM program to generate 2,2,4,6,10 upto 10th term.
DECLARE SUB FIBO()
CLS
EXECUTE FIBO
END
SUB FIBO
A=2
B=2
FOR Ctr=5 to 1
DISPLAY A;B;
A=A+B
B=A+B
NEXT Ctr
END FUNCTION

Solution:

DECLARE SUB FIBO()
CLS
CALL FIBO
END
SUB FIBO
A=2
B=2
FOR Ctr=5 to 1 STEP -1
PRINT A;B;
A=A+B
B=A+B
NEXT Ctr
END SUB

Q2)

DECLARE FUNCTION reverse$(N$)
INPUT "Any string";N$
X$=reverse$(N$)
PRINT N$
END
FUNCTION reverse (N$)
L=LEN$(N$)
FOR X=L to 1 STEP -1
A$=MID$(N$,X,1)
B$=B$+A$
NEXT X
B$=reverse$(N$)
END SUB

Solution:

DECLARE FUNCTION reverse$(N$)
INPUT "Any string";N$
X$=reverse$(N$)
PRINT X$
END
FUNCTION reverse$(N$)
L=LEN(N$)
FOR X=L to 1 STEP -1
A$=MID$(N$,X,1)
B$=B$+A$
NEXT X
reverse$=B$
END SUB

Q3)

REM To store name and age in a sequental data gile STD.DOC
OPEN STD.DOC FOR OUT AS#1
INPUT "Enter name";N
INPUT "Enter age";A
WRITE 1,N$,A
CLOSE #1
END

Solution:

OPEN "STD.DOC" FOR OUTPUT AS #1
INPUT "Enter name";N$
INPUT "Enter age";A
WRITE #1,N$,A
CLOSE #1
END

Q4)

REM To store name and age in a sequential data file REC.DAT
CLS
OPEN "Employee.dat" FOR OUTPUT AS #1
DO
INPUT "Enter employee's name";N$
INPUT "Enter employee's address";A$
INPUT "Enter employee's age";A1
INPUT "Enter employee's gender";G$
INPUT "Enter employee's salary";S
WRITE #1,A$,A1,G$,S
INPUT "Add more records(Y/N)";A
LOOP WHILE UCASE(A$)="Y"
CLOSE 1
END

Solution:

OPEN "REC.DAT" FOR OUTPUT AS #1
DO
INPUT "Enter employee's name";N$
INPUT "Enter employee's age";A1
WRITE #1,N$,A1
INPUT "Add more records(Y/N)";A$
LOOP WHILE UCASE$(A$)="Y"
CLOSE #1
END

Q5)

CLS
OPEN "check.dat" FOR INPUT AS #1
DO WHILE NOT EOF(3)
INPUT #1,N$,D$,PH,A$
PRINT "Name=";N$
PRINT "DOB=";D$
PRINT "Phone=";PH
PRINT "Address=";A
LOOP
CLOSE #
END

Solution:

CLS
OPEN "check.dat" FOR INPUT AS #1
DO WHILE NOT EOF(1)
INPUT #1,N$,D$,PH,A$
PRINT "Name=";N$
PRINT "DOB=";D$
PRINT "Phone=";PH
PRINT "Address=";A$
LOOP
CLOSE #1
END

Q6)

CLS
OPEN "MARKS.DAT" FOR INPU AS #1
PRINT "Roll Number","Name","English","Nepali","Maths"
DO WHILE NOT EOF()
INPUT #1,RN,N$,E,Ne,M
PRINT R,N$,E,Ne,M
END WHILE
CLOSE #1
END

Solution:

CLS
OPEN "MARKS.DAT" FOR INPUT AS #1
PRINT "Roll Number","Name","English","Nepali","Maths"
DO WHILE NOT EOF(1)
INPUT #1,RN,N$,E,Ne,M
PRINT RN,N$,E,Ne,M
LOOP
CLOSE #1
END