#include<bits/stdc++.h>
using namespace std;
#define mod 1000000007
#define inf 1e8
#define pb push_back
#define mp make_pair
#define Int long long
#define fs first
#define sc second
#define pll pair<Int,Int>
#define pii pair<int,int>
#define piiii pair<pii, pii>
#define MAX 100005
#define LOGN 20
#define gcd __gcd
#define swap(x,y) x^=y^=x^=y
#define optimise_stuff ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
Int modpow(Int a,Int b,Int m){Int c=1;while(b){if(b&1)c=(c*a)%m;b/=2;a=(a*a)%m;}return c;}



int main(){

	optimise_stuff;
	
	string s;int n, i, j = 0, a[4] = {0};

	cin>>n;
	cin>>s;

	for(i = 0; i < n; i++){
		if(s[i] >= '0' && s[i] <= '9')
			a[0] = 1;
		if(s[i] >= 'a' && s[i] <= 'z')
			a[1] = 1;
		if(s[i] >= 'A' && s[i] <= 'Z')
			a[2] = 1;
		if(s[i] == '!' || s[i] == '@' || s[i] == '#' || s[i] == '$' ||
			s[i] == '%' || s[i] == '^' || s[i] == '&' || s[i] == '*' ||
			s[i] == '(' || s[i] == ')' || s[i] == '-' || s[i] == '+' )
			a[3] = 1;
	}

	for(i =0, j = 0; i < 4; i++){
		j += (1 - a[i]);
	}

	n += j;

	if(n < 6)
		j += 6 - n;
	cout<<j<<endl;
	return 0;
}