Cod sursa(job #1965663)

Utilizator Tiberiu55Ionescu Tiberiu Tiberiu55 Data 14 aprilie 2017 15:42:16
Problema Evaluarea unei expresii Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 1.08 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream in("evaluare.in");
ofstream out("evaluare.out");
const int  N=100001;
char s[N];
int p;
int expresie();
int termen();
int factor();

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

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

}
int factor()
{
    int val=0,semn=1;
    while(s[p]=='-')
    {
        semn=-semn;
        p++;
    }
    if(s[p]=='(')
    {
        p++;
        val=expresie();
        p++;///pentru )
        return semn*val;
    }
    while(s[p]>='0'&&s[p]<='9')
    {
        val=val*10+(s[p]-'0');
        p++;
    }
    return semn*val;
}
int main()
{
    in>>s;
    out<<expresie();
}