Cod sursa(job #1200009)

Utilizator tudormaximTudor Maxim tudormaxim Data 21 iunie 2014 15:22:31
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.22 kb
#include <cstdio>
#define L 100001
using namespace std;
char s[L];
int p=0;
int expresie();
int termen();
int factor();
int expresie()
{
    int sum=termen();
    while(s[p]=='+' || s[p]=='-')
    {
        if(s[p]=='+')
        {
            p++;
            sum=sum+termen();
        }
        else
        {
            p++;
            sum=sum-termen();
        }
    }
    return sum;
}
int termen()
{
    int prod=factor();
    while(s[p]=='*' || s[p]=='/')
    {
        if(s[p]=='*')
        {
            p++;
            prod=prod*factor();
        }
        else
        {
            p++;
            prod=prod/factor();
        }
    }
    return prod;
}
int factor()
{
    int val=0,semn=1;
    while(s[p]=='-')
    {
        p++;
        semn=-semn;
    }
    if(s[p]=='(')
    {
        p++;
        val=expresie();
        p++;
        return semn*val;
    }
    while(s[p]>='0' && s[p]<='9')
        val=val*10+(s[p++]-'0');
    return semn*val;
}
int main()
{
    freopen("evaluare.in","r",stdin);
    freopen("evaluare.out","w",stdout);
    int n;
    gets(s);
    n=expresie();
    printf("%d",n);
    fclose(stdin);
    fclose(stdout);
    return 0;
}