Looping Through a File

Here is a program that reads 15 numbers from NUMS.DAT and computes their sum.

OPEN "NUMS.DAT" FOR INPUT AS #7  ' Open the file

LET SUM = 0                      ' Initialize the sum
LET COUNT = 1                    ' Count from 1 to 15
DO WHILE COUNT <= 15             ' Loop once per count
  INPUT #7, NUM                  ' Read one number
  LET SUM = SUM + NUM            ' Add it to the sum
  LET COUNT = COUNT + 1          ' Count up by one
LOOP

PRINT "SUM is", SUM              ' Print out the results
END

This is an ordinary loop that controls the number of times the INPUT statement is executed. Each time, a number is read in and added to SUM.

You could improve the program by having it ask the user for the file name and by using a FOR loop.