[子程序] 调用子程序为读取数据为动态数组赋值报错

program main 
  implicit none
  character,allocatable:: A(:,:)
  integer:: m,n,nx,ny
  character(len=200):: filename
  integer:: i,j,iunit,mbc
  filename="d:\2.txt"
  nx=2
  ny=2
  allocate(A(nx,ny))
  call read_txt(A,1,filename,m,n,nx,ny)
  
  print*,A
  end program

subroutine  read_txt(input,iunit,filename,m,n,nx,ny)
  implicit none
  !函数内部变量声明
  integer:: iunit,m,n
  integer:: nx,ny
  character(len=200):: filename
  character(len=200):: input(nx,ny)
  !局部变量
  integer:: i,j
  character(len=200):: line
  character,allocatable:: temp(:)
  
  open(unit=iunit,file=filename)
  read(iunit,"(a)")line
  read(line,*)m,n
  
  allocate(temp(n))
  do i=1,m
    read(iunit,"(a)")line
    read(line,*)(temp(j),j=1,n)
    do j=1,n
      !print*,temp(j)
      input(i,j)=temp(j)
    enddo
  enddo
  close(iunit)
  end subroutine

subroutine  read_txt(input,iunit,filename,m,n,nx,ny)
  implicit none
  !函数内部变量声明
  integer:: iunit,m,n
  integer:: nx,ny,i
  character(len=200):: filename
  character:: input(nx,ny)
  !局部变量
  open(unit=iunit,file=filename)
  read(iunit,*) m,n
  do i = 1 , m
    read(iunit,*) input(i,:n)
  end do  
end subroutine