#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) begin(v),end(v)
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
using ll = long long;
using pii = pair<int, int>;
constexpr ll INF = 1ll<<30;
constexpr ll longINF = 1ll<<60;
constexpr ll MOD = 1000000007;
constexpr bool debug = false;
//---------------------------------//

int main() {
	string S;
	cin >> S;
	
	auto f1 = [&](auto f1, int & pos) -> int {
		// (, or number
		int res = 0;
		if (S[pos] == '(') {
			++pos;
			res = f1(f1, pos);
			++pos;
		}
		else {
			res = S[pos++] - '0';
			while (pos < S.size() && S[pos] != ')') {
				char op = S[pos++];
				int n = f1(f1, pos);
				if (op == '+') res += n;
				else res -= n;
			}
		}
		return res;
	};
	
	int pos = 0;
	cout << f1(f1, pos) << endl;
}