Fortran Fortran90 problem, runtime error

[Saxby]

Hello, I've been playing around with some code (as shown below) and for some reason everytime i run this code I am told:

At line 11 of file tester.f90
Fortran runtime error: End of file

I'm not really sure what's causing it, is it the position of my Open file?
Any help would be much aprrieiated :)

PROGRAM tester

!Turn off implicit typing
IMPLICIT NONE

INTEGER :: a, b

OPEN(10,FILE='tester.out')

WRITE(10,*) 'Please give value for a'
READ(10,*) a

IF (a < 0) THEN
WRITE(10,*) 'Wrong number'
STOP
END IF

WRITE(10,*) 'Please give value for b'
READ(10,*) b

IF (b > 0) THEN
WRITE(10,*) 'Wrong number'
STOP
END IF

WRITE(10,*) a * b

CLOSE(10)

END PROGRAM tester

 

[SteamKing]

Are you sure the file exists?

You are writing to the file and reading from it simultaneously. This can cause problems if not done carefully.

When opening the file, FORM ='FORMATTED' should probably be used.