Pagini recente » Cod sursa (job #694735) | Cod sursa (job #2838967) | Cod sursa (job #320165) | Cod sursa (job #2937356) | Cod sursa (job #2612271)
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
ifstream in("evaluare.in");
ofstream out("evaluare.out");
string s;
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++;///pentru (
val = expresie();
p++;///pentru )
return semn * val;
}
while (s[p] >= '0' && s[p] <= '9')
{
val = val * 10 + (s[p] - '0');
p++;
}
return semn * val;
}
int main()
{
in >> s;
in.close();
out << expresie();
out.close();
return 0;
}