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#include <fstream>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
const long MAX = 100010;
char S[MAX], *p=S;
long termen();
long factor();
long eval() {
long r = termen();
while ( *p=='+' || *p=='-' ) {
switch ( *p ) {
case '+':
++p;
r += termen();
break;
case '-':
++p;
r -= termen();
break;
}
}
return r;
}
long termen() {
long r = factor();
while ( *p=='*' || *p=='/' ) {
switch ( *p ) {
case '*' :
++p;
r *= factor();
break;
case '/':
++p;
r /= factor();
break;
}
}
return r;
}
long factor() {
long r=0;
if ( *p == '(' ) {
++p;
r = eval();
++p;
} else {
while ( *p>='0' && *p<='9' ) {
r = r*10 + *p - '0';
++p;
}
}
return r;
}
int main() {
fin.get(S,MAX);
fout<<eval();
return 0;
}