#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n;
	scanf("%d",&n);
	char str[n+1];
	scanf("%s",str);
	int i=0,digit=0,low_alpha=0,upper_alpha=0,special=0,mini=0;
	while(str[i]!='\0')
	{
		if(str[i]>='0'&& str[i]<='9')
		digit++;
		else if(str[i]>='a' && str[i]<='z')
		low_alpha++;
		else if(str[i]>='A' && str[i]<='Z')
		upper_alpha++;
		else
		special++;
		i++;
	}
	if(digit==0)
	mini++;
	if(low_alpha==0)
	mini++;
	if(upper_alpha==0)
	mini++;
	if(special==0)
	mini++;
	if(n<6)
	mini=max(mini,6-n);
	printf("%d\n",mini);
	return 0;
}