#include<bits/stdc++.h>
using namespace std;
stack<int> stk1;
stack<char> stk2;
void cal()
{
	int b=stk1.top();stk1.pop();
	int a=stk1.top();stk1.pop();
	char ch=stk2.top();stk2.pop();
	if(ch=='+')
	{
		stk1.push(a+b);
	}
	if(ch=='-')
	{
		stk1.push(a-b);
	}
	if(ch=='*')
	{
		stk1.push(a*b);
	}
	if(ch=='/')
	{
		stk1.push(a/b);
	}
	if(ch=='^')
	{
		int t=1;
		for(int i=1;i<=b;i++)
		{
			t=t*a;
		}
		stk1.push(t);
	}
}
int main()
{
	string str;
	cin>>str;
	map<char,int> h={{'+',1},{'-',1},{'*',2},{'/',2},{'^',3}};
	int n=str.size();
	for(int i=0;i<n;i++)
	{
		if(str[i]=='@')
		{
			break;
		}
		if(str[i]>='0'&&str[i]<='9')
		{
			int t=0;
			while(str[i]>='0'&&str[i]<='9')
			{
				t=t*10+str[i]-'0';
				i++;
			}
			stk1.push(t);
			i--;
			continue;
		}
		if(str[i]=='(')
		{
			stk2.push('(');
			continue;
		}
		if(str[i]==')')
		{
			while(stk2.top()!='(')
			{
				cal();
			}
			stk2.pop();
			continue;
		}
		while(stk2.size()&&h[str[i]]<=h[stk2.top()])
		{
			cal();
		}
		stk2.push(str[i]);
	}
	while(stk2.size())
	{
		cal();
	}
	cout<<stk1.top();
	return 0;
}