Modify Fizz Buzz in Fortran (#5119)

Improve Fizz Buzz Fortran code snippet

Author: pascalecu

archive/f/fortran/fizz-buzz.f95

@@ -1,16 +1,23 @@
-program fizz_buzz
-        integer :: i
+program fizzbuzz
+   implicit none
+   integer, parameter :: n = 100
+   integer :: i
 
-        do i = 1,100
-                if ((modulo(i,3) == 0) .and. (modulo(i,5) == 0)) then 
-                        write (*,'(a)') "FizzBuzz"
-                else if (modulo(i,3) == 0) then
-                        write (*,'(a)') "Fizz"
-                else if (modulo(i,5) == 0) then
-                        write (*,'(a)') "Buzz"
-                else
-                        write (*,'(I0)') i
-                end if
-        end do
-        
-end program fizz_buzz
+   do i = 1, n
+      write(*,'(A)') fizzbuzz_string(i)
+   end do
+
+contains
+
+   pure function fizzbuzz_string(x) result(str)
+      integer, intent(in) :: x
+      character(len=8) :: str
+
+      str = ''
+
+      if (mod(x,3) == 0) str = 'Fizz'
+      if (mod(x,5) == 0) str = trim(str)//'Buzz'
+      if (len_trim(str) == 0) write(str,'(I0)') x
+   end function fizzbuzz_string
+
+end program fizzbuzz