Cod sursa(job #1123950)

Utilizator andreismara97Smarandoiu Andrei andreismara97 Data 26 februarie 2014 10:45:08
Problema Evaluarea unei expresii Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 1.23 kb
#include<cstdio>
using namespace std;
char v[100005];
int p;

int expresie();
int termen();
int factor();

int expresie()
{
    int sum=termen();
    while(v[p]=='+' || v[p]=='-')
    {
        if(v[p]=='+')
        {
            p++;
            sum=sum+termen();
        }
        if(v[p]=='-')
        {
            p++;
            sum=sum-termen();
        }
    }
    return sum;
}

int termen()
{
    int prod=factor();
    while(v[p]=='*' || v[p]=='/')
    {
        if(v[p]=='*')
        {
            p++;
            prod=prod*termen();
        }
        if(v[p]=='/')
        {
            p++;
            prod=prod/termen();
        }
    }
    return prod;
}

int factor()
{
    int val=0,semn=1;
    if(v[p]=='-')
    {
        semn=-1;
        p++;
    }
    if(v[p]=='(')
    {
        p++;  //trec peste '('
        val=expresie();
        p++;  //trec peste ')'
        return semn*val;
    }
    while(v[p]>='0' && v[p]<='9')
    {
        val=val*10+(v[p]-'0');
        p++;
    }
    return semn*val;
}


int main()
{
    freopen("evaluare.in","r",stdin);
    freopen("evaluare.out","w",stdout);
    scanf("%s",v);
    printf("%d",expresie());
    return 0;
}