Syntax error when using “X != 0” in Fortran

Question

I have a problem with my Fortran program that does nothing more than calculating a prime factorization (or should do). That\'s the error:

C:\\MinGW\\Fortran>         


        

Answer 1

Well, this is Fortran and ! denotes a comment. So the compiler actually sees

if (prim(i) 

which is no valid statement. The error message you see reflects that.

"Not equal" in Fortran is /= or .ne.:

 if (prim(i) /= 0 .and. modulo(n, prim(i)) == 0) then

and, later on:

if (prim(i) /= 0) then