Cod sursa(job #2531603)

Utilizator ale.sicobeanAlexandra Sicobean ale.sicobean Data 26 ianuarie 2020 14:55:08
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.14 kb
#include <bits/stdc++.h>

using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");

string s;
int x;

bool op1(int ind)
{
    if(s[ind]=='+' || s[ind]=='-')
        return 1;
    else
        return 0;
}

bool op2(int ind)
{
    if(s[ind]=='*' || s[ind]=='/')
        return 1;
    else
        return 0;
}

int factor(int &ind)
{
    int eval(int &a);
    int nr=0;
    if(s[ind]=='(')
    {
        int nr=eval(++ind);
        ind++;
        return nr;
    }
    else
        while(ind<=s.size() && isdigit(s[ind]))
    {
        nr=nr*10+s[ind]-'0';
        ind++;
    }
    return nr;
}

int termen(int &ind)
{
    int p=factor(ind);
    while(ind<=s.size() && op2(ind))
    {
        if(s[ind]=='*')
            p*=factor(++ind);
        else
            p/=factor(++ind);
    }
    return p;
}

int eval(int &ind)
{
    int a=termen(ind);
    while(ind<=s.size() && op1(ind))
    {
        if(s[ind]=='+')
            a+=termen(++ind);
        else
            a-=termen(++ind);
    }
    return a;
}

int main()
{
    fin>>s;
    fout<<eval(x);
    return 0;
}