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#include <bits/stdc++.h>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
bool delim(char c) {
return c == ' ';
}
bool is_op(char c) {
return c == '+' || c == '-' || c == '*' || c == '/';
}
int priority (char op) {
if (op == '+' || op == '-') {
return 1;
}
if (op == '*' || op == '/') {
return 2;
}
return -1;
}
void process_op(stack<int>& st, char op) {
int r = st.top(); st.pop();
int l = st.top(); st.pop();
switch (op) {
case '+': st.push(l + r); break;
case '-': st.push(l - r); break;
case '*': st.push(l * r); break;
case '/': st.push(l / r); break;
}
}
int evaluate(string& s) {
stack<int> st;
stack<char> op;
for (int i = 0; i < (int)s.size(); i++) {
if (delim(s[i])) {
continue;
}
if (s[i] == '(') {
op.push('(');
} else if (s[i] == ')') {
while (op.top() != '(') {
process_op(st, op.top());
op.pop();
}
op.pop();
} else if (is_op(s[i])) {
char cur_op = s[i];
while (!op.empty() && priority(op.top()) >= priority(cur_op)) {
process_op(st, op.top());
op.pop();
}
op.push(cur_op);
} else {
int number = 0;
while (i < (int)s.size() && isalnum(s[i])) {
number = number * 10 + s[i++] - '0';
}
--i;
st.push(number);
}
}
while (!op.empty()) {
process_op(st, op.top());
op.pop();
}
return st.top();
}
int main() {
string s;
fin >> s;
fout << evaluate(s);
return 0;
}