Cod sursa(job #2842100)

Utilizator bogdan007Bogdan Patrascu bogdan007 Data 31 ianuarie 2022 09:25:56
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.25 kb
#include <fstream>
#include <cstring>

using namespace std;

ifstream cin ("evaluare.in");
ofstream cout ("evaluare.out");

const int N = 100001;
char s[N];
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++; /// trece peste (
        val = expresie();
        p++; /// trece peste )
        return semn * val;
    }
    while(isdigit(s[p]))
    {
        val = val * 10 + (s[p] - '0');
        p++;
    }
    return semn * val;
}

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