#include <bits/stdc++.h>
using namespace std;
int main(void) {
 int n;
 cin >> n;
  string s;
  cin >> s;
  int dig=0, lo=0, hi=0, sp=0;
  for(char c: s) {
   if(c<='9'&&c>='0') {
    ++dig;
   } else if(c <= 'z' && c>='a') {
    ++lo;
   } else if(c<='Z'&&c>='A'){
    ++hi;
   } else {
    ++sp;
   }
  }
  
  int ans1 = 0, ans2 = 0;
  if(dig == 0) ++ans1;
  if(lo == 0) ++ans1;
  if(hi == 0) ++ans1;
  if(sp == 0) ++ans1;
  ans2 = max(6-(int)s.size(), 0);
  cout << max(ans2, ans1) << '\n';
}