Cod sursa(job #1320182)

Utilizator moise_alexandruMoise Alexandru moise_alexandru Data 17 ianuarie 2015 18:11:38
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.06 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream in("evaluare.in");
ofstream out("evaluare.out");
char T[100005];
int i=0;
long evalueaza();
long factor();
long numar()
{
    long rezultat=0;
    if(T[i]=='(')
    {
        i++;
        rezultat=evalueaza();
        i++;
    }
    else
    {
        while(T[i]>='0' && T[i]<='9')
        {
            rezultat=rezultat*10+(T[i]-'0');
            i++;
        }
    }
    return rezultat;
}
long factor()
{
    long r=numar();
    while(T[i] == '*' || T[i] == '/') {
        if(T[i]=='*')
        {
            i++;
            r=r*numar();
        }
        else if(T[i]=='/')
        {
            i++;
            r=r/numar();
        }
    }
    return r;
}
long evalueaza()
{
    long r=factor();
    while(T[i] == '-' || T[i] == '+') {
        if(T[i]=='-')
            i++,r=r-factor();
        else if(T[i]=='+')
            i++,r=r+factor();
    }
    return r;
}
int main()
{
    in.getline(T,100005);
    out<<evalueaza();
    return 0;
}