Cod sursa(job #1088190)

Utilizator cristigrigoreGrigore Cristan Andrei cristigrigore Data 20 ianuarie 2014 11:46:21
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <cstdio>
#include <cstring>
using namespace std;

int i,j,r;
char *p, s[100013];

int tm();

int eval();

int factor();



int main()
{
    freopen("evaluare.in","r",stdin);
    freopen("evaluare.out","w",stdout);
    gets(s);
    p=s;
    i=eval();
    printf("%d",i);

    return 0;
}
int eval()
{
    int r=tm();
      while(*p=='+' || *p=='-')
        {if(*p=='+')
        {
            p++;
            r+=tm();
        }
        else if(*p=='-')
        {
            p++;
            r-=tm();
        }
        }
    return r;
}
int tm()
{
    int r=factor();
    while(*p=='*' || *p=='/')
    {if(*p=='*')
    {
        p++;
        r*=factor();
    }
    else if(*p=='/')
    {
        p++;
        r/=factor();

    }}
    return r;
}
int factor()
{
    int r=0;
    if(*p=='(')
    {
        p++;
        r=eval();
        p++;
    }
    while(*p<='9' && *p>='0')
    {
        r*=10;
        r+=*p-'0';
        p++;
    }
    return r;
}