Cod sursa(job #2115738)

Utilizator MarianConstantinMarian Constantin MarianConstantin Data 27 ianuarie 2018 09:30:53
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.15 kb
#include <iostream>
#include <fstream>
#define N 100010

char a[N];
int n, i=0;

long long termen();
long long factor();

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

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

long long factor()
{
    long long r=0;
    if (a[i]=='(')
    {
        i++;
        r=expresie();
        i++;
    }
    else
    {
        while (a[i]>='0' && a[i]<='9')
        {
            r=r*10+(a[i]-48);
            i++;
        }
    }
    return r;
}

using namespace std;

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