Cod sursa(job #2271300)

Utilizator marian013Giugioiu Marian Constantin marian013 Data 28 octombrie 2018 13:09:40
Problema Evaluarea unei expresii Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.98 kb
#include <fstream>
using namespace std;
char s[100010],*p=s;
long termen();
long factor();
long eval(){
    long r=termen();
    while(*p=='+'||*p=='-')
        if(*p=='+')
        {
            ++p;
            r+=termen();
            break;
        }
        else
        {
            ++p;
            r-=termen();
            break;
        }
    return r;
}
long termen(){
    long r=factor();
    while(*p=='*'||*p=='/')
        if(*p=='*')
        {
            ++p;
            r*=factor();
        }
        else
        {
            ++p;
            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-'0';
            ++p;
        }
    }
    return r;
}
int main()
{
    ifstream f("evaluare.in");
    ofstream g("evaluare.out");
    f>>s;
    g<<eval();
}