#include<iostream>
#include<algorithm>
using namespace std;
using lint=int64_t;

string S;
int cur;

int expr();
int term();
int num();

int expr()
{
	int ret=0;
	ret=term();
	
	for(;;)
	{
		if(S[cur]=='+')
		{
			cur++;
			ret+=expr();
		}
		else if(S[cur]=='-')
		{
			cur++;
			ret-=expr();
		}
		else 
			break;
	}
	//cout << "expr:" << ret << endl;
	return ret;
}

int term()
{
	int ret=0;
	ret=num();

	if(S[cur]=='(')
	{
		cur++;
		ret=expr();
	}
	else if(S[cur]==')')
		cur++;

	//cout << "term:" << ret << endl;
	return ret;
}

int num()
{
	int ret=0;
	if('0'<=S[cur] && S[cur]<='9')
	{
		ret=S[cur]-'0';
		cur++;
	}
	//cout << "num:" << ret << endl;
	return ret;
}

int main()
{
	cin >> S;

	cout << expr() << endl;
	//cout << cur << endl;
	return 0;
}