#include <bits/stdc++.h>

using namespace std;

#define si(x) scanf("%d", &x)
#define sll(x) scanf("%lld", &x)
#define PB push_back
#define MP make_pair


string A[4] = {"0123456789", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOPQRSTUVWXYZ", "!@#$%^&*()-+"};

int main() 
{   
    int n; string a;
    cin >> n >> a;
    int N = n;
    int bt = 0;
    for (auto c : a)
    {
        for (int i = 0; i < 4; i++)
            if (A[i].find(c) != string::npos)
                bt |= (1<<i);
    }
    for (int i = 0; i < 4; i++)
        if (( (bt>>i) & 1 )== 0 )
            n++;
    if (n < 6) n = 6;
    cout << n - N  << endl;
    return 0;
}