Cod sursa(job #3215659)

Utilizator Maftei_TudorMaftei Tudor Maftei_Tudor Data 15 martie 2024 11:23:46
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.09 kb
#include <iostream>
#include <cstring>

using namespace std;

int i;
char c[100005];

int eval();
int factor();
int termen();

int main()
{
    freopen("evaluare.in", "r", stdin);
    freopen("evaluare.out", "w", stdout);
    cin.tie(nullptr)->sync_with_stdio(0);

    cin >> c;
    cout << eval();
    return 0;
}

int eval() {
    int r = termen();
    while(c[i] == '+' || c[i] == '-') {
        if(c[i] == '+') {
            i++;
            r += termen();
        }
        else {
            i++;
            r -= termen();
        }
    }

    return r;
}
int termen() {
    int r = factor();
    while(c[i] == '*' || c[i] == '/') {
        if(c[i] == '*') {
            i++;
            r *= factor();
        }
        else {
            i++;
            r /= factor();
        }
    }

    return r;
}
int factor() {
    int r = 0;
    if(c[i] == '(') {
        i++;
        r = eval();
        i++;
    }
    else {
        while(isdigit(c[i])) {
            r = r * 10 + c[i] - '0';
            i++;
        }
    }

    return r;
}