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#include <fstream>
char s[100002];
int i;
int expresie();
int termen();
int factor();
int main()
{
std::ifstream fin("evaluare.in");
std::ofstream fout("evaluare.out");
fin >> s;
i = 0;
fout << expresie();
}
int expresie()
{
int r = termen(); // calculam primul termen
while(s[i] == '+' || s[i] == '-')
{
if(s[i] == '+')
{
i++; // sarim peste +
r += termen();
}
else
{
i++; // sarim peste -
r -= termen();
}
}
return r;
}
int termen()
{
int r = factor();
while(s[i] == '*' || s[i] == '/')
{
if(s[i] == '*')
{
i++; // sarim peste *
r *= factor();
} else
{
i++; // sarim peste /
r /= factor();
}
}
return r;
}
int factor()
{
int r;
if(s[i] == '(') // expresie
{
i++;
r = expresie();
i++;
} else // numar
{
r = 0;
while(s[i] >= '0' && s[i] <= '9')
{
r = r*10 + (s[i] - '0');
i++;
}
}
return r;
}