Cod sursa(job #2871936)

Utilizator Glue02Tudorescu Ioan Daniel Glue02 Data 16 martie 2022 00:13:06
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.81 kb
#include <fstream>
using namespace std;

ifstream cin("evaluare.in");
ofstream cout("evaluare.out");
char s[100001];
int fact();
int elem();
int i=0;
int eval()
{
    int r=elem();
    while(s[i]=='+'||s[i]=='-')
    {
        if(s[i]=='+') i++,r+=elem();
        else i++,r-=elem();
    }
    return r;
}
int elem()
{
    int r=fact();
    while(s[i]=='*'||s[i]=='/')
    {
        if(s[i]=='*') i++,r*=fact();
        else i++,r/=fact();
    }
    return r;
}
int fact()
{
    int r=0;
    if(s[i]=='(')
    {
        i++;
        r=eval();
        i++;
    }
    else
    {
        while(isdigit(s[i]))
        {
           r=r*10+s[i]-'0';
           i++;
        }
    }
    return r;
}

int main()
{
    cin.getline(s,100001);
    i=0;
    cout<<eval();
    return 0;
}