#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string p) {
    // Return the minimum number of characters to make the password strong
    int i,ans=0,c=0,c1=0,c2=0,c3=0;
    for(i=0;i<n;i++)
    {
        if(p[i]>=48 && p[i]<=57)
            c=1;
    }
    if(c==0)
        ans++;
    for(i=0;i<n;i++)
    {
        if(p[i]>=65 && p[i]<=90)
            c1=1;
    }
    if(c1==0)
        ans++;
    for(i=0;i<n;i++)
    {
        if(p[i]>=97 && p[i]<=122)
            c2=1;
    }
    if(c2==0)
        ans++;
    for(i=0;i<n;i++)
    {
        if(p[i]=='!'||p[i]=='@'||p[i]=='#'||p[i]=='$'||p[i]=='%'||p[i]=='^'||p[i]=='&'||p[i]=='*'||p[i]=='('||p[i]==')'||p[i]=='-'||p[i]=='+')
            c3=1;
    }
    if(c3==0)
        ans++;
    if(n+ans<6)
        ans+=6-n-ans;
    return ans;
}

int main() {
    int n;
    cin >> n;
    string password;
    cin >> password;
    int answer = minimumNumber(n, password);
    cout << answer << endl;
    return 0;
}