Cod sursa(job #2677677)

Utilizator Titus_Teodor_PirsanTitus-Teodor Pirsan Titus_Teodor_Pirsan Data 27 noiembrie 2020 10:24:10
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.16 kb
#include <iostream>
#include <fstream>

using namespace std;
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 produs = factor();
    while (s[p] == '*' || s[p] == '/') {
        if (s[p] == '*') {
            p++;
            produs *= factor();
        }
        else {
            p++;
            produs /= factor();
        }
    }
    return produs;
}
int factor() {
    int val = 0, semn = 1;
    while (s[p] == '-') {
        p++;
        semn = -semn;
    }
    if (s[p] == '(') {
        p++;
        val = expresie();
        p++;
        return semn * val;
    }
    while ('0' <= s[p] && s[p] <= '9') {
        val = val * 10 + (s[p++] - '0');
    }
    return semn * val;
}
int main()
{
    ifstream in("evaluare.in");
    ofstream out("evaluare.out");
    in >> s;
    out << expresie();
}