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#include <fstream>
#include <stack>
#include <cstring>
#include <cmath>
using namespace std;
ifstream fin("input.txt");
ofstream fout("output.txt");
char s[100010];
int n, p = 0;
stack<char> op;
stack<long long> nr;
long long eval(long long x, long long y, char semn) {
switch(semn) {
case '+': return x+y;
case '-': return x-y;
case '*': return x*y;
case '/': return x/y;
case '^': return pow(x,y);
}
}
long long nextnum() {
long long numar = 0;
while(s[p] >= '0' && s[p] <= '9')
numar = numar*10 + (s[p++]-'0');
return numar;
}
int prioritate(char s1, char s2) {
if(s1 == '(')
return 1;
if((s1 == '-' || s1 == '+') && (s2 == '*' || s2 == '/' || s2 == '^'))
return 1;
if((s1 == '*' || s1 == '/') && s2 == '^')
return 1;
return 0;
}
void fill_op_nr() {
int n = strlen(s);
while(p < n) {
switch(s[p]) {
case '(': {
op.push(s[p++]);
break;
}
case ')': {
while(op.top() != '(') {
long long v2 = nr.top();
nr.pop();
long long v1 = nr.top();
nr.pop();
char semn = op.top();
op.pop();
nr.push(eval(v1, v2, semn));
// fout << semn << ' ';
}
op.pop();
p++;
break;
}
case '+':
case '-':
case '*':
case '/':
case '^': {
if(op.empty() || prioritate(op.top(), s[p]) == 1) {
op.push(s[p++]);
}
else {
do {
long long v2 = nr.top();
nr.pop();
long long v1 = nr.top();
nr.pop();
char semn = op.top();
op.pop();
nr.push(eval(v1, v2, semn));
//fout << semn << ' ';
} while(!op.empty() && prioritate(op.top(), s[p]) == 0);
}
break;
}
default:
nr.push(nextnum());
//fout << nr.top() << ' ';
}
}
while(!op.empty()) {
long long v2 = nr.top();
nr.pop();
long long v1 = nr.top();
nr.pop();
char semn = op.top();
op.pop();
nr.push(eval(v1, v2, semn));
//fout << semn << ' ';
}
}
int main() {
fin.getline(s, 100010);
n = strlen(s);
fill_op_nr();
fout << nr.top();
return 0;
}