#include <iostream>
using namespace std;

int main() {
	int x = 0, a;
	string s;
	while (cin >> s){
		if (s == "multiply") {
			cin >> a;
			x*=a;
		}
		if (s == "subtract") {
			cin >> a;
			x-=a;
		}
		if (s == "add") {
			cin >> a;
			x+=a;
		}
	}
	cout << x;
	return 0;
}