Cod sursa(job #1647122)

Utilizator stefan_gheorgheGheorghe Stefan stefan_gheorghe Data 10 martie 2016 19:06:16
Problema Evaluarea unei expresii Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 0.76 kb
#include <fstream>
#include <cstring>
using namespace std;
ifstream f("evaluare.in");
ofstream g("evaluare.out");
char s[100011],*p;
int n;
int eval();
int termen();
int factor();
int main()
{
    f.getline(s,100011),p=s,g<<eval();
    return 0;
}
int eval()
{int r=termen();
    while(*p=='+' || *p=='-')
    {
        if (*p=='+'){++p,r+=termen();break;}
        if (*p=='-'){++p,r-=termen();break;}
    }
    return r;
}
int termen()
{int r=factor();
    while(*p=='*' || *p=='/')
    {
        if (*p=='*'){++p,r*=factor();break;}
        if (*p=='/'){++p,r/=factor();break;}
    }
    return r;
}
int factor()
{int r=0;
    if (*p=='(') ++p,r=eval(),++p;
    else while('0'<=*p && *p<='9') r*=10,r+=(int)*p-'0',++p;
    return r;
}