#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef string str;
int main()
{
    str s;
    cin >> s;
    stringstream ss(s);
    ll n;
    char o;
    vector<ll> st;
    ss >> n;
    st.push_back(n);
    while (ss >> o >> n)
    {
        if (o == '*')
        {
            ll t = st.back();
            st.pop_back();
            st.push_back(t * n);
        }
        else if (o == '+') st.push_back(n);
    }
    ll ans = 0;
    for (ll x : st) ans += x;
    cout << ans;
    return 0;
}