   Program ABC159B
   implicit none
   integer::n,m,i,j,judge
   character(100)::s,t,

      read(*,*) s
      n=len_trim(s)
      t=s(1:(n-1)/2)
      m=len_trim(t)

      do i=1,(n-1)/2
         if (s(i:i)/=s(n-i+1:n-i+1)) then
            judge=0
            exit
         else
            judge=1
         end if
      end do

      if (judge==1) then
         do j=1,m/2
            if(t(j:j)/=t(m-j+1:m-j+1)) then
               judge=0
               exit
            else
               judge=1
            end if
         end do
      end if

      if (judge==1) then
         print *,'Yes'
      else
         print *,'No'
      end if
      stop

   End program ABC159B