Intel Visual Fortran

Examples:

Hello, World!:

program HelloWorld
print *, 'Hello, World!'
end program HelloWorld

Factorial:

This example uses iterative factorial definition. Format specifiers I and A are used for printing integers and strings, respectively. Trying to calculate 13! produces an arithmetic overflow error, so last lines of program output look like this:

13! = 1932053504
14! = 1278945280
15! = 2004310016
16! = 2004189184

 program Factorial
 integer :: f,n
 f = 1
 n = 0
 
 do
 print '(I2, A, I10)', n, "! = ", f
 n = n + 1
 f = f * n
 if (n==17) then
 exit
 end if
 end do
 end program Factorial

Fibonacci numbers:

This example uses iterative definition of Fibonacci numbers. The tricky part is printing the calculated values in one line, without leading or trailing spaces. Format specifier (I3, A, $) means that first an integer is printed using exactly 3 positions, followed by a string. The final $ suppresses trailing carriage return, used by default, so that everything is printed in one line.

 program Fibonacci
 integer :: f1,f2,f3,i
 i = 1
 f1 = 0
 f2 = 1
 
 do
f3 = f2 + f1
 f1 = f2
 f2 = f3
 i = i + 1
 if (f1<10) then
 print '(I1, A, $)', f1, ', '
 elseif (f1<100) then
 print '(I2, A, $)', f1, ', '
 else
 print '(I3, A, $)', f1, ', '
 end if
 if (i==17) then
 exit
 end if
 end do

 print *, '...'
 end program Fibonacci