Computer Science 161

Professor Valente

An Example of early BASIC progamming

The Algorithm:

Set the value of Sum to 0

Get a value for X

While X is not 0

Set the value of Sum to Sum + X

Get a value for X

End While

Print the value of Sum

Stop

Our VSC-32 assembly language program to solve this problem:

LOAD Zero

STORE Sum

READ X

While: LOAD X

JUMP Print

LOAD Sum

ADD X

STORE Sum

READ X

LOAD Zero

JUMP While

Print: WRITE Sum

STOP

Zero: DATA 0

Sum: DATA 0

X: DATA 0

An Early BASIC program to solve this problem:

10 SUM = 0

20 INPUT X

30 IF X = 0 THEN 60

40 SUM = SUM + X

50 GOTO 20

60 PRINT “SUM = ”, SUM

70 END