#include <bits/stdc++.h>
#define mem( a , b ) memset( a , b , sizeof(a) )
using namespace std;
int _I(){ int x ; scanf("%d",&x); return x; }
struct node{
        int s , d;
        node(){};
        node ( int x , int y )
        {
                s = x;
                d = y;
        }
};
int dx[ 5 ] = { 1 , -1 , 0 , 0 };
int dy[ 5 ] = { 0 , 0 , 1 , -1 };
int dp[ 1001 ][ 1024 ];
const int mod = 100000007;
void solve()
{
        string ss = "!@#$%^&*()-+";
        int n = _I();
        string s;
        cin>>s;
        int cnt = 4;
        bool flag[ 4 ];
        mem( flag , 0 );
        for( int i = 0 ; i < n ; i++ )
        {
                if( (s[ i ] >= '0' && s[ i ] <= '9') ) flag[ 0 ] = 1 ; if ( s[ i ] >= 'A' && s[ i ] <= 'Z' ) flag[ 1 ] = 1 ;  if (s[ i ] >= 'a' && s[ i ] <= 'z')  flag[ 2 ] = 1;
                else{
                        int sz = ss.size();
                        for( int j = 0 ; j < sz ; j++ )
                        {
                                if( s[ i ] == ss[ j ] ) flag[ 3 ] = 1;
                        }
                }
        }
        if( n < 6 )
        {
                int f = cnt-(flag[ 0 ] + flag[ 1 ] + flag[ 2 ] + flag[ 3 ]);
                int ans = n + f;
                if( ans < 6 ) ans += ( 6 - (n+f) );
                printf("%d\n", ans - n);
        }
        else{
                printf("%d\n", cnt - ( flag[ 0 ] + flag[ 1 ] + flag[ 2 ] + flag[ 3 ] ) );
        }
}
int main()
{
         //freopen("input.txt","r",stdin);
        //freopen("output.txt","w",stdout);
        //int t = _I();
        //while( 1 )
        solve();
	return 0;
}