Cod sursa(job #2529594)

Utilizator Mada2003Madalina Scarlat Mada2003 Data 23 ianuarie 2020 17:58:58
Problema Evaluarea unei expresii Scor 60
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.31 kb
#include <fstream>
#include <algorithm>

using namespace std;

const int NMAX = 100005;

ifstream cin("evaluare.in");
ofstream cout("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
        if(s[p] == '-')
        {
            p++;
            sum -= termen();
        }
    }
    return sum;
}

int termen()
{
    int prod = factor();
    while(s[p] == '*' || s[p] == '/')
    {
        if(s[p] == '*')
        {
            p++;
            prod *= termen();
        }
        else
        if(s[p] == '/')
        {
            p++;
            prod /= termen();
        }
    }
    return prod;
}

int factor()
{
    int val = 0, semn = 1;
    while(s[p] == '-')
    {
        p++;
        semn = - semn;
    }
    if(s[p] == '(')
       {
           p++;
           val = expresie();
           p++;
           return semn * val;
       }
    while(s[p] >= '0' && s[p] <= '9')
    {
        val = val * 10 + (s[p] - '0');
        p++;
    }
    return semn * val;
}

int main()
{
    cin >> s;
    cout << expresie();
    return 0;
}