Cod sursa(job #1858288)

Utilizator StefanTufisTufis Stefan StefanTufis Data 27 ianuarie 2017 12:23:59
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.96 kb
#include <fstream>
#include <cstring>
using namespace std;
ifstream f("evaluare.in");
ofstream g ("evaluare.out");
char s[100001],*p=s;
long termen();
long factor();
long eval()
{
    long r=termen();
    while(*p=='+' || *p=='-')
        if(*p=='+')
        {
            p++;
            r=r+termen();
        }
        else
        {
            p++;
            r=r-termen();
        }
    return r;
}
long termen()
{
    long r=factor();
    while(*p=='*' || *p=='/')
        if(*p=='*')
        {
            p++;
            r=r*factor();
        }
        else
        {
            p++;
            r=r/factor();
        }
    return r;
}
long factor()
{
    long r=0;
    if(*p=='(')
    {
        p++;
        r=eval();
        p++;
    }
    else while(*p>='0' && *p<='9')
    {
        r=r*10+*p-48;
        p++;
    }
    return r;
}
int main()
{
    f.getline(s,100001);
    g<<eval();
    return 0;
}