Cod sursa(job #1651078)

Utilizator savigunFeleaga Dragos-George savigun Data 12 martie 2016 01:21:35
Problema Evaluarea unei expresii Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.22 kb
#include <iostream>
#include <fstream>
using namespace std;

char s[100001], p=0;

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

int expresie()
{
    int sum = termen();

    while (s[p] == '+' || s[p] == '-')
    {
        if (s[p] == '+')
        {
            p++;
            sum += termen();
        }
        if (s[p] == '-')
        {
            p++;
            sum -= termen();
        }

    }

    return sum;

}
int termen ()
{
    int prod = factor();
    while ( s[p]=='*'||s[p]=='/')
    {
        if ( s[p] == '*' )
        {
            p++;
            prod*=factor();
        }
        else
        {
            p++;
            prod/=factor();
        }
    }
    return prod;
}

int factor()
{
    int val = 0,semn = 1;
    while(s[p] == '-')
    {
        semn=-semn;
        p++;
    }
    if(s[p] == '(')
    {
        p++;
        val=expresie();
        p++;
        return semn*val;
    }
    while(s[p] >= '0' && s[p] <= '9')
    {
        val = val*10 + (s[p]-'0');
        p++;
    }
    return semn*val;
}
int main()
{


    ifstream fin ("evaluare.in");
    ofstream fout ("evaluare.out");


    fin>>s;
    fout<<expresie();
}