Cod sursa(job #2869591)

Utilizator Diana_IonitaIonita Diana Diana_Ionita Data 11 martie 2022 17:54:23
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.09 kb
#include <bits/stdc++.h>

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

string s;
int i=0;
long long eval();
long long termen();
long long factor();
long long eval()
{
    long long r=termen();
    while(s[i]=='+'||s[i]=='-')
    {
        if(s[i]=='+')
        {
            i++;
            r+=termen();

        }
        else
        {
            i++;
            r-=termen();

        }
    }
    return r;
}
long long termen()
{
    long long r=factor();
    while(s[i]=='*'||s[i]=='/')
    {
        if(s[i]=='*')
        {
            i++;
            r*=factor();


        }
        else
        {
            i++;
            r/=factor();

        }
    }
    return r;
}
long long factor()
{
    long long r=0;
    if(s[i]=='(')
    {
        i++;
        r=eval();
        i++;
    }
    else
    {
        while('0'<=s[i]&&s[i]<='9')
        {
            r=r*10+(s[i]-'0');
            i++;
        }
    }
    return r;
}
int main()
{
    fin>>s;
    fout<<eval();

    return 0;
}