#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, char password[]) {
    // Return the minimum number of characters to make the password strong"!@#$%^&*()-+"
    int count=0;
    int isdigit=0,ischar=0,isup=0,isspecial=0;
    for(int i=0;i<n;i++){
        if(password[i]>='0'&&password[i]<='9'){
            isdigit=1;
        }
        else if(password[i]>='a'&&password[i]<='z'){
            ischar=1;
        }
        else if(password[i]>='A'&&password[i]<='Z'){
            isup=1;
        }
        else if(password[i]=='!'||password[i]=='@'||password[i]=='#'||password[i]=='%'||password[i]=='^'||password[i]=='&'||password[i]=='*'||password[i]=='('||password[i]==')'||password[i]=='-'||password[i]=='+'){
            isspecial=1;
        }
    }
    if(isspecial&&isup&&ischar&&isdigit&&strlen(password)>=6){
        return 0;
    }
    else{
        count=isspecial+isup+ischar+isdigit;
        count=4-count;
        if(strlen(password)+count<6){
            count=count+(6-(strlen(password)+count));
        }
    }
    return count;
}

int main() {
    int n;
    cin >> n;
    char password[101];
    cin >> password;
    int answer = minimumNumber(n, password);
    cout << answer << endl;
    return 0;
}