Cod sursa(job #2320237)

Utilizator verde.cristian2005Verde Flaviu-Cristian verde.cristian2005 Data 14 ianuarie 2019 15:42:54
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.06 kb
#include <fstream>
using namespace std;
ifstream in("evaluare.in");
ofstream out("evaluare.out");
char s[100001];

int p=1;

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