Cod sursa(job #1651074)

Utilizator savigunFeleaga Dragos-George savigun Data 12 martie 2016 01:15:18
Problema Evaluarea unei expresii Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.14 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();
        }else
        {
            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;
    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 cin("evaluare.in");
ofstream cout("evaluare.out");

cin.get(s, 100000);

cout<<expresie();

    return 0;
}