PROGRAM ATCODER

implicit none
integer :: n,i,j,count=0,count_a=0,count_b=0
character(len=10),allocatable :: s(:)

read*, n
allocate(s(n))
read*, s(1:n)

do i = 1, n
  do j = 1, len_trim(s(i))-1
    if ( s(i)(j:j+1) == 'AB' ) then
      count = count + 1
    end if
  end do
  if ( s(i)(1:1) == 'B' ) then
      count_b = count_b + 1
    end if   
    if ( s(i)(len_trim(s(i)):len_trim(s(i))) == 'A' ) then
      count_a = count_a + 1
    end if
end do

print'(i0)',  count + min(count_a,count_b)

END PROGRAM ATCODER