Cod sursa(job #3005002)

Utilizator biancalautaruBianca Lautaru biancalautaru Data 16 martie 2023 18:46:37
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.89 kb
#include <fstream>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
int i;
char s[100001];
int expresie();
int termen();
int factor();

int expresie() {
    int r=termen();
    while (s[i]=='+' || s[i]=='-') {
        i++;
        if (s[i-1]=='+')
            r+=termen();
        else
            r-=termen();
    }
    return r;
}

int termen() {
    int r=factor();
    while (s[i]=='*' || s[i]=='/') {
        i++;
        if (s[i-1]=='*')
            r*=factor();
        else
            r/=factor();
    }
    return r;
}

int factor() {
    int r=0;
    if (s[i]=='(') {
        i++;
        r=expresie();
        i++;
    }
    else
        while (s[i]>='0' && s[i]<='9') {
            r=r*10+s[i]-'0';
            i++;
        }
    return r;
}

int main() {
    fin>>s;
    i=0;
    fout<<expresie();
    return 0;
}