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#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <cmath>
#include <list>
#include <map>
#include <set>
#include <string>
#include <sstream>
#include <bitset>
using namespace std;

typedef long long int LL;
typedef long double LD;
typedef vector<int> VI;
typedef vector<LL> VLL;
typedef vector<LD> VLD;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef vector<PII> VPII;

const int INF = 1000000001;
const LD EPS = 10e-9;

#define FOR(x, b, e) for(int x = b; x <= (e); ++x)
#define FORD(x, b, e) for(int x = b; x >= (e); --x)
#define REP(x, n) for(int x = 0; x < (n); ++x)
#define VAR(v, n) __typeof(n) v = (n)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int)(x).size())
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define MP make_pair
#define PB push_back
#define ST first
#define ND second
#define abs(a) ((a)<0 ? -(a) : (a))
#define max(a, b) ((a) > (b) ? (a) : (b))
#define min(a, b) ((a) < (b) ? (a) : (b))

struct Clause
{
	// > 0 to normalne xi, < 0 znaczy zaprzeczenie xi
	vector<int> x; 
};

struct Formula
{
	vector<Clause> clauses;
};

int n, maxSet, countSets;
string s;
Formula formula;

int toInt(const string& s)
{
	istringstream iss(s);
	int num;
	iss >> num;
	
	return num;	
}

void createClause(Clause& clause, int& idx)
{
	while(idx < s.size() && s[idx] != ')')
	{
		if(s[idx] == ' ' || s[idx] == '(' || s[idx] == 'v')
		{
			idx++;
			continue;
		}
		
		bool orig = true;
		if(s[idx] == '~')
		{
			orig = false;
			idx++;
		}
		
		if(s[idx++] != 'x')
		{
			cout << "cos sie schrzanilo..." << endl;
			cout << "idx-1: " << idx-1 << ", s[idx-1]: " << s[idx-1] << endl;
		}
		
		string numberS;
		while(isdigit(s[idx]))
		{
			numberS.push_back(s[idx]);
			idx++;
		}
		
		int number = toInt(numberS);
		
		if(orig)
		{
			clause.x.push_back(number);
		}
		else
		{
			clause.x.push_back(-number);
		}
	}
	
	idx++;
}

void createFormula()
{
	int idx = 0;
	while(idx < s.size())
	{
		while(s[idx] != '(')
		{
			idx++;
		}
		
		formula.clauses.push_back(Clause());
		createClause(*formula.clauses.rbegin(), idx);	
	}	
}

void printClause(const Clause& clause)
{
	cout << "clause:" << endl;
	for(int x : clause.x)
	{
		if(x > 0)
		{
			cout << 'x' << x << ' ';
		}
		else
		{
			cout << "~x" << -x << ' ';
		}
	}
	cout << endl;
	cout << "----" << endl;
}

void printFormula()
{
	for(const auto& clause : formula.clauses)
	{
		printClause(clause);	
	}
}

bool getXValue(int xs, int x)
{	
	int absX = abs(x);
	bool res = xs&(1<<(absX-1));
	res = x > 0 ? res : !res;
	
	//cout << "xs: " << xs << ", x:" << x << ", res: " << res << endl;
	
	return res;
}

bool evaluateClause(const Clause& clause, int xs)
{
	for(int x : clause.x)
	{
		if(getXValue(xs, x))
		{
			return true;
		}
	}
	
	return false;	
}

bool evaluateFormula(int xs)
{
	for(const auto& clause : formula.clauses)
	{
		if(!evaluateClause(clause, xs))
		{
			return false;
		}
	}	
	
	return true;
}

int main()
{
	cin >> n;
	getchar();
	getline(cin, s);
	
	//cout << n << endl;
	//cout << s << endl;
	
	maxSet = (1<<n) - 1;
	createFormula();
	
	//printFormula();
	
	for(int i = 0; i <= maxSet; ++i)
	{
		if(evaluateFormula(i))
		{
			countSets++;
			
			//bitset<32> bs(i);
			//cout << "true dla xs = "  << i << " (" << bs << ")" << endl; 
		}
		
		//cout << "------" << endl;
	}
	
	cout << countSets << endl;
	
	return 0;
}