Cod sursa(job #2068548)

Utilizator andrei2000mAndrei Moldoveanu andrei2000m Data 18 noiembrie 2017 08:53:58
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include <fstream>

using namespace std;
ifstream f("evaluare.in");
ofstream g("evaluare.out");
char s[100001],*p;
int eval();
int termen();
int factor();
int main()
{
    f.getline(s,100000);
    p=s;
    g<<eval();
    g.close();
    return 0;
}
int eval()
{
    int r;
    r=termen();
    while(*p=='+'||*p=='-')
        if(*p=='+') {++p;r+=termen();}
        else {++p;r-=termen();}
    return r;
}
int termen()
{
    int r;
    r=factor();
    while(*p=='*'||*p=='/')
        if(*p=='*') {++p;r*=factor();}
        else {++p;r/=factor();}
    return r;
}
int factor()
{
    int r=0;
    if(*p=='(')\
    {
        ++p;
        r=eval();
        ++p;
    }
    else
        while(*p>='0'&&*p<='9')
        {
            r=r*10+(int)*p-'0';
            ++p;
        }
    return r;
}