program integral
      IMPLICIT REAL*8 (A-H,O-Z)
      IMPLICIT INTEGER*4 (I-N)
      write(6,*)' N, ax, ay, az, nx, ny, nz:'
      read(5,*)N,ax,ay,az,nx,ny,nz
      pi=4.0d0*atan(1.0d0)
      akx=pi*dble(nx)/ax
      aky=pi*dble(ny)/ay
      akz=pi*dble(nz)/az
      ak2=akx**2+aky**2+akz**2
      dx=2.0d0*ax/dble(N)
      dy=2.0d0*ay/dble(N)
      dz=2.0d0*az/dble(N)
      sr=0.0d0
      si=0.0d0
      x=-ax-dx/2.0d0
      do 1 ix=1,N
      x=x+dx
      xx=x**2
      skx=akx*x
      y=-ay-dy/2.0d0
      do 1 iy=1,N
      y=y+dy
      yy=xx+y**2
      sky=skx+aky*y
      z=-az-dz/2.0d0
      do 1 iz=1,N
      z=z+dz
      zz=yy+z**2
      skz=sky+akz*z
      dd=1.0d0/dsqrt(zz)
      si=si-sin(skz)*dd
1     sr=sr+cos(skz)*dd
      sr=sr*dx*dy*dz
      si=si*dx*dy*dz
      v=ax*ay*az
      write(6,*)'Real:',sr,sr/(4.0d0*pi/ak2)
      write(6,*)'Imag:',si,si/(4.0d0*pi/ak2)
c
      stop
      end