#include <bits/stdc++.h>
#define ll long long 
using namespace std;

int main()
{ll int n,i,c=0,ans=0,c1=0,c2=0,c3=0,c4=0;
string s;
cin>>n;
cin>>s;
for(i=0;i<n;i++)
{
    if(s[i]>='a'&&s[i]<='z')
    c1++;
    else if(s[i]>='A'&&s[i]<='Z')
    c2++;
    else if(s[i]>=48 &&s[i]<=57)
    c3++;
    else if(s[i]=='!'||s[i]=='@'||s[i]=='#'||s[i]=='$'||s[i]=='%'||s[i]=='^'||s[i]=='&'||s[i]=='*'||s[i]=='('||s[i]==')'||s[i]=='-'||s[i]=='+')
    c4++;
    
}
if(c1==0)
c++;
if(c2==0)
c++;
if(c3==0)
c++;
if(c4==0)
c++;
if(n+c<6)
ans=6-n;
else ans=c;



    cout << ans << endl;
    return 0;
}