#include <bits/stdc++.h>
#define mod 1000000007
using namespace std;
/*hello stalker
Any data or information stolen is copyright infringement. You  will be reported.*/
long long int i,j,k,t,q,n,m,xm,ym,ii,jj,kk,iii,jjj,row,col,fcost,nn,mm;
long long int  fl;
string s,s1[22],s2,s3;
char c,c1;
long long int fco,co,eo,oo,panga,cou,oj,ojv;
map <long long,long long> map1,map2,mapp;
long long int y[3000005],z[3000005],yf[3000000],a[100002][100],x[1002][10002];
set <long long int> set1,set2;
vector<long long>  v,v1,vv;
vector<string> vs;
double floa,flo;
vector<tuple<long long,long long,long long> > vt;
vector<pair<long long,long long> > vp;

int main(){cin>>panga;
cin>>s;
s1[0]="0123456789";
s1[1]="abcdefghijklmnopqrstuvwxyz";
s1[2]="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
s1[3]="!@#$%^&*()-+";
for(i=0;i<s.length();i++)
{
    for(j=0;j<4;j++)
    {
        for(ii=0;ii<s1[j].length();ii++)
        {
            if(s1[j][ii]==s[i])
            {
                y[j]=1;
            }
        }
    }
}
for(i=0;i<4;i++)
{
    if(y[i]==0)
    {
        co++;
    }
}
if(s.length()<6)
{row=s.length();
    fco=abs(6-row);
}
cout<<max(co,fco);
return 0;}