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#include <fstream>
#include <cstring>
using namespace std;
ifstream in("evaluare.in");
ofstream out("evaluare.out");
const int N = 1e5;
char s[N+1];
int p;
int expresie();
int termen();
int factor();
int expresie()
{
int sum = termen();
while(s[p] == '+' || s[p] == '-')
{
if (s[p] == '+')
{
p++;
sum += termen();
}
else
{
p++;
sum -= termen();
}
}
return sum;
}
int termen()
{
int prod = factor();
while(s[p] == '*' || s[p] == '/')
{
if (s[p] == '*')
{
p++;
prod *= factor();
}
else
{
p++;
prod /= factor();
}
}
return prod;
}
int factor()
{
int val = 0, semn = 1;
while (s[p] == '-')
{
p++;
semn = -semn;
}
if (s[p] == '(')
{
p++;
val= expresie();
p++; /// pentru ')'
return semn * val;
}
///stim ca am ajuns la o constanta
while (s[p] >= '0' && s[p] <= '9')
{
val = val * 10 + s[p]-'0';
p++;
}
return semn * val;
}
int main()
{
in >> s;
p=0;
out<<expresie();
return 0;
}