#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <cstring>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int N;
    cin>>N;
    bool dig = false, lcase = false, ucase = false, spec = false;
    for(int i = 0; i < N; ++i)
    {
        char a;
        cin>>a;
        if(isupper(a))
            ucase = true;
        if(islower(a))
            lcase = true;
        if(isdigit(a))
            dig = true;
        switch(a)
        {
            case '!':
            case '@':
            case '#':
            case '$':
            case '%':
            case '^':
            case '&':
            case '*':
            case '(':
            case ')':
            case '-':
            case '+':
                spec = true;
        }
    }
    int count = 0;
    if(!ucase)
        ++count;
    if(!lcase)
        ++count;
    if(!dig)
        ++count;
    if(!spec)
        ++count;
    count = max(count, 6 - N);
    cout<<count;
    return 0;
}