Cod sursa(job #2230785)

Utilizator ciutanpCiuta Andrei Calin ciutanp Data 11 august 2018 14:42:09
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.92 kb
#include<bits/stdc++.h>
using namespace std;

ifstream f("evaluare.in");
ofstream g("evaluare.out");

char s[100005],*p=s;
long termen();
long factor();

long eval()
{
    long r=termen();
    while(*p=='+' || *p=='-')
    {
        if(*p=='+')
           ++p, r+=termen();
        else
        {
            ++p, r-=termen();
        }

    }
    return r;
}

long termen()
{
    long r=factor();
    while(*p=='*' || *p=='/')
    {
        if(*p=='*')
        {
            ++p;
            r*=factor();

        }
        else
        {
            ++p;
            r/=factor();
        }
    }
    return r;
}

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

int main()
{
    f.get(s,100005);
    g<<eval();
}