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#include <fstream>
#include <string>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
string s;
int termen(int &ind);
int factor(int &ind);
int eval(int &ind);
bool is_op1(char l)
{
if(l=='+' || l=='-')
return 1;
return 0;
}
bool is_op2(char l)
{
if(l=='*' || l=='/')
return 1;
return 0;
}
int factor(int &ind)
{
if(s[ind]=='(')
{
ind++;
int sum=eval(ind);
ind++;
return sum;
}
int nr=0;
while(ind<=s.size() && isdigit(s[ind]))
{
nr=nr*10+s[ind++]-'0';
}
return nr;
}
int termen(int &ind)
{
int p=factor(ind);
while(ind!=s.size() && is_op2(s[ind]))
{
if(s[ind]=='*')
p*=factor(++ind);
else
p/=factor(++ind);
}
return p;
}
int eval(int &ind)
{
int sign;
int a=termen(ind);
while(ind!=s.size() && is_op1(s[ind]))
{
sign=1;
if(s[ind]=='-')
sign=-1;
a+=sign*termen(++ind);
}
return a;
}
int main()
{
fin>>s;
int i=0;
fout<<eval(i);
return 0;
}