Cod sursa(job #1278179)

Utilizator tudorcomanTudor Coman tudorcoman Data 28 noiembrie 2014 16:47:24
Problema Evaluarea unei expresii Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.03 kb
#include <cstdio>
#define LMAX 100003
using namespace std;
freopen("evaluare.in","r",stdin);
freopen("evaluare.out","w",stdout);
char x[LMAX];
int i;
int eval();
int termen();
int factor();

int eval(){
    int r = termen();
    while(x[i] == '+' || x[i] == '-'){
        if(x[i] == '+'){
            ++i;
            r += termen();
        }
        if(x[i] == '-'){
            ++i;
            r -= termen();
        }
    }
    return r;
}
int termen(){
    int r = factor();
    while(x[i] == '*' || x[i] == '/'){
        if(x[i] == '*'){
            ++i;
            r *= factor();
        }
        if(x[i] == '/'){
            ++i;
            r /= factor();
        }
    }
    return r;
}
int factor(){
    int r = 0;
    if(x[i] == '('){
        ++i;
        r = eval();
        ++i;
    }else{
        while(x[i] <='9' && x[i] >='0'){
            r = r*10 + x[i]-'0';
            ++i;
        }
    }
    return r;
}
int main()
{
    gets(x);
    printf("%d\n",eval());
    return 0;
}