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#include <fstream>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
char s[100001], *p = s;
long eval();
long termen();
long factor();
int main()
{
fin.getline(s, 100001);
fout << eval();
return 0;
}
long eval()
{
long n = termen();
while(*p == '+' || *p == '-')
{
switch(*p)
{
case '+':
p++;
n += termen();
break;
case '-':
p++;
n -= termen();
break;
}
}
return n;
}
long termen()
{
long n = factor();
while(*p == '*' || *p == '/')
{
switch(*p)
{
case '*':
p++;
n *= termen();
break;
case '/':
p++;
n /= termen();
break;
}
}
return n;
}
long factor()
{
long n = 0;
if(*p == '(')
{
p++;
n = eval();
p++;
}
else
{
while(*p >= '0' && *p <= '9')
{
n = n * 10 + *p - '0';
p++;
}
}
return n;
}