Cod sursa(job #2528080)

Utilizator mihnea03Ciocioiu Mihnea mihnea03 Data 21 ianuarie 2020 14:29:57
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1 kb
#include <fstream>

using namespace std;
char a[100010];
int i;

int expresie();
int factor();
int termen();

int main() {
    ifstream fin("evaluare.in");
    ofstream fout("evaluare.out");
    fin>>a;
    fout<<expresie();
    return 0;
}

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

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

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