-module(solution).
-export([main/0]).

main() ->
  {ok, [N]} = io:fread("", "~d"),
  {ok, [S]} = io:fread("", "~s"),
  M = missing(N, S),
  io:format("~p", [M]),
  true.


missing(N, S) ->
  {Digits, Lower, Upper, Special} = check(S),
  case Digits < 1 of 
    true ->
      M1 = 1;
    false ->
      M1 = 0
  end,
  case Lower < 1 of 
    true ->
      M2 = M1+1;
    false ->
      M2 = M1
  end,
  case Upper < 1 of 
    true ->
      M3 = M2+1;
    false ->
      M3 = M2
  end,
  case Special < 1 of 
    true ->
      M4 = M3+1;
    false ->
      M4 = M3
  end,
  case N < 6 of
    true ->
      max(M4, 6-N);
    false ->
      M4
  end.


check(S) ->
  Digits = 0,
  Lower = 0,
  Upper = 0,
  Special = 0,
  check(S, Digits, Lower, Upper, Special).

check([], Digits, Lower, Upper, Special) ->
  {Digits, Lower, Upper, Special};
check([H|T], Digits, Lower, Upper, Special) when H >= $0 andalso H =< $9 ->
  check(T, Digits+1, Lower, Upper, Special);
check([H|T], Digits, Lower, Upper, Special) when H >= $a andalso H =< $z ->
  check(T, Digits, Lower+1, Upper, Special);
check([H|T], Digits, Lower, Upper, Special) when H >= $A andalso H =< $Z ->
  check(T, Digits, Lower, Upper+1, Special);
check([H|T], Digits, Lower, Upper, Special) when 
  H =:= $! orelse
  H =:= $@ orelse
  H =:= $# orelse
  H =:= $$ orelse
  H =:= $% orelse
  H =:= $^ orelse
  H =:= $& orelse
  H =:= $* orelse
  H =:= $( orelse
  H =:= $) orelse
  H =:= $- orelse
  H =:= $+ ->
  check(T, Digits, Lower, Upper, Special+1);
check([_H|T], Digits, Lower, Upper, Special) ->
  check(T, Digits, Lower, Upper, Special).