Cod sursa(job #2528256)

Utilizator vlddvlad motoi vldd Data 21 ianuarie 2020 18:04:13
Problema Evaluarea unei expresii Scor 70
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.04 kb
#include <bits/stdc++.h>
using namespace std;

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

char s[100001],*p;

int eval();
int termen();
int factor();

int main()
{
    int rez;
    f.getline(s,1000);
    p=s;
    rez=eval();
    g<<rez;
}

int eval()
{
    int r=termen();

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


int termen()
{
    int r=factor();

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

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


int factor()
{
    int r=0;

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