＜SUBROUTINE Example Program＞

Program subroutine_example
  Real x1,x2
  Call shiki(1.0,3.0,2.0,x1,x2)
  Print *, x1,x2
End
Subroutine shiki(a,b,c,x1,x2)
  Real, Intent(In) :: a,b,c
  Real, Intent(Out) :: x1,x2
  tmp = b**2 - 4.0*a*c
  x1 = (-b+Sqrt(tmp))/(2.0*a)
  x2 = (-b-Sqrt(tmp))/(2.0*a)
End Subroutine shiki

■ Execution Results

  -1.0000000  -2.0000000