Mai intai trebuie sa te autentifici.

Cod sursa(job #1330653)

Utilizator ovidiuz98Zamfir Ovidiu ovidiuz98 Data 30 ianuarie 2015 20:53:58
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.96 kb
#include <fstream>

using namespace std;

ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
int i;
char s[100002];
int termen();
int factor();
int expresie(){
    int r=termen();
    while(s[i]=='+' || s[i]=='-')
        if(s[i]=='+'){
            i++;
            r+=termen();
        }
        else{
            i++;
            r-=termen();
        }
    return r;
}
int termen(){
    int r=factor();
    while(s[i]=='*' || s[i]=='/')
        if(s[i]=='*'){
            i++;
            r*=factor();
        }
        else{
            i++;
            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;
    fout<<expresie();
    fin.close();fout.close();
    return 0;
}