      implicit real*8 (a-h, o-z)
      pi=2.d0*asin(1.d0)
      m=6
      n=10
      syu=2.0d0*pi*26.5d-3
      h=104.5d-3
      r=syu/m/(2.0d0*sin(pi/m))
      atusa=0.4d-3
      print*,"初期高さ"
      read*,a
      dh=h/n
      dh2=a*dh
      print*,"変位量"
      read*,s
      p=1000d0
      k=p/s
      print*,"ばね定数は:",k
      E=2800d6
      A=(r**2-(r-(atusa/cos(pi/m)))**2)*((m*sin(2*pi/m))/2)
      o=(k*dh2)/(E*A)
      print*,"無次元化バネ定数は:",o
      end
