#include <iostream>
#include <vector>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
	int minLength = 6;
	int minDigits = 1;
	int minUpperChars = 1;
	int minLowerChars = 1;
	vector<char> specialChars = { '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '-', '+'};

	int n;
	cin >> n;
	string s;
	cin >> s;

	int length = s.length();
	int countDigits = 0;
	int countUpperChars = 0;
	int countLowerChars = 0;
	int countSpecialChars = 0;
	
	for (int i = 0; i < s.length(); i++)
	{
		if (isdigit(s[i]))
		{
			countDigits++;
		}
		else if (isupper(s[i]))
		{
			countUpperChars++;
		}
		else if (islower(s[i]))
		{
			countLowerChars++;
		}
		else if (find(specialChars.begin(), specialChars.end(), s[i]) != specialChars.end())
		{
			countSpecialChars++;
		}
	}

	int totalOp = 0;

	if (countDigits == 0)
	{
		totalOp++;
	}

	if (countUpperChars == 0)
	{
		totalOp++;
	}

	if (countLowerChars == 0)
	{
		totalOp++;
	}

	if (countSpecialChars == 0)
	{
		totalOp++;
	}

	if (length + totalOp < minLength)
	{
		totalOp += (minLength - (length + totalOp));
	}

	cout << totalOp << endl;

	return 0;
}