Распараллеливание циклов в OpenMP

program laba5
integer::i, n, j, k
real::dx,dy,dt
real, allocatable::u(:,:,:)
 
write(*,*) 'n = '
read(*,*) n
!write(*,*) 'dx = '
!read(*,*) dx
!write(*,*) 'dy = '
!read(*,*) dy
!write(*,*) 'dt = '
!read(*,*) dt
dt=0.001
dx=1.0/n
dy=dx
 
allocate(u(n+3,n+3,n+3))
call cpu_time(start)
 
!$OMP PARALLEL
    
do k=1,n
 
    do i=2,n
 
!$OMP DO
        do j=2,n
        u(1,j,k)=f(i*dy,j*dt)
        u(n,j,k)=f(i*dy,j*dt)
        u(i,1,k)=f(i*dx,j*dt)
        u(i,n,k)=f(i*dx,j*dt)
        u(i,j,1)=f(i*dx,j*dy)
        end do
    !$OMP END DO
 
    end do
        
end do
    
 
    
!$OMP END PARALLEL   
 
call cpu_time(finish)
write(*,*) finish-start
 do i=2,n
    do j=2,n
        do k=1,n       
        u(i,j,k+1)=k1(i*dx,j*dy)*(u(i+1,j,k)-2*u(i,j,k)+u(i-1,j,k))
        u(i,j,k+1)=u(i,j,k+1)/(dx*dx)
        u(i,j,k+1)=u(i,j,k+1)+k2(i*dx,j*dy)*(u(i,j+1,k)-2*u(i,j,k)+u(i,j-1,k))/(dy*dy)
        u(i,j,k+1)=u(i,j,k+1)+g(i*dx,j*dy,k*dt)
        u(i,j,k+1)=u(i,j,k+1)*dt+u(i,j,k)
        end do
    end do
end do
open(12,FILE='res',STATUS='REPLACE', ACTION='WRITE')
!WRITE(12,*) 'RESULTS: 22'
WRITE(12,*)(((u(i,j,k),j=2,n),i=2,n),k=2,n)
close(12)
 
deallocate(u)
write(*,*) 'end'
end