#include <bits/stdc++.h>

using namespace std;
int main() {
    int n;
    cin >> n;
    string p;
    cin >> p;
 if(n>=6){int a=0;int b=0;int c=0;int d=0;
        for(int i=0;i<n;i++){
            if(p[i]>=48 && p[i]<=57)a++;
            if(p[i]>=65 && p[i]<=90)b++;
            if(p[i]>=97 && p[i]<=122)c++;
         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]=='@')d++;
            
        }int g=0;
        if(a>=1 && b>=1 && c>=1 && d>=1)cout<<"0";
                    else {if(a<1)g++;
                         if(b<1)g++;
                          if(c<1)g++;
                          if(d<1)g++;
                            cout<<g;
                         }
               
    }
    else{
    int a=0;int b=0;int c=0;int d=0;
        for(int i=0;i<n;i++){
            if(p[i]>=48 && p[i]<=57)a++;
            if(p[i]>=65 && p[i]<=90)b++;
            if(p[i]>=97 && p[i]<=122)c++;
            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]=='@')d++;
            
        }int g=0;
     
                    if(a<1)g++;
                         if(b<1)g++;
                          if(c<1)g++;
                          if(d<1)g++;
                         
        if(n+g<6)cout<<6-n;
        else cout<<g;
    }
    return 0;
}