program main
  !
  ! Sample program of input
  !
  implicit none
  real :: a,b,c,d,e,f

  write(*,*) 'Input a and b'
  write(*,*) 'a = ?'
  read(*,*) a
  write(*,*) 'b = ?'
  read(*,*) b

  c=a+b
  d=a-b
  e=a*b
  f=a/b

  write(*,*) a,'+',b,'=',c
  write(*,*) a,'-',b,'=',d
  write(*,*) a,'*',b,'=',e
  write(*,*) a,'/',b,'=',f

end program main

実行結果