#include <bits/stdc++.h>

using namespace std;

#define MOD 1000000007
#define pb push_back
#define mp make_pair
#define all(c) (c).begin(),(c).end()
#define sz(a) int((a).size())
#define F first
#define S second

#define rep(i, a, b) for(int i = a; i < b; ++i)
#define per(i, a, b) for(int i = a; i >= b; --i)
#define travel(c,itr) for(__typeof((c).begin()) itr=(c).begin();itr!=(c).end();itr++)
#define INDEX(arr,ind)          (lower_bound(all(arr),ind)-arr.begin())

#define scan(x) do{while((x=getchar())<'0'); for(x-='0'; '0'<=(_=getchar()); x=(x<<3)+(x<<1)+_-'0');}while(0)
char _;


typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef pair<ll,int> pli;
typedef pair<ll,ll> pll;
typedef pair<int, pii> piii;
typedef pair<ll, pll> plll;
typedef vector<pii> vpii;
typedef vector<piii> vpiii;

inline ll powmod(ll x, ll n, ll _mod){ 
  ll res = 1; 
  while (n){
    if (n & 1)res = (res*x) % _mod; 
    x = (x*x) % _mod; 
    n >>= 1;
    }
    return res; 
  }

#define N 100005
int n;
string s;
int cnt[300];

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    // freopen("in.txt", "r", stdin);
    // freopen("out.txt", "w", stdout);
    cin>>n;
    cin>>s;
    string x = "!@#$%^&*()-+";
    rep(i,0,n)cnt[s[i]]++;
    int ans=0;
    int ok=0;
    for(char c='a';c<='z';c++)if(cnt[c])ok=1;
    if(!ok)ans++,n++;
    ok=0;
    for(char c='A';c<='Z';c++)if(cnt[c])ok=1;
    if(!ok)ans++,n++;
    ok=0;
    for(char c='0';c<='9';c++)if(cnt[c])ok=1;
    if(!ok)ans++,n++;
    ok=0;
    rep(i,0,sz(x)){
        if(cnt[x[i]])ok=1;
    }
    if(!ok)ans++,n++;
    ok=0;
    ans+=max(6-n,0);
    cout<<ans<<'\n';
    return 0;
}