Cod sursa(job #3216720)

Utilizator AndPitAndreeaPiticar AndPit Data 19 martie 2024 12:18:59
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.08 kb
#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
ifstream f("evaluare.in");
ofstream g("evaluare.out");
int pos;
string s;
int add();
int fact()
{
    int x=0;
    if(s[pos]=='(')
    {
        ++pos;
        x=add();
        ++pos;
    }
    else while(s[pos]>='0' && s[pos]<='9')
        {
            x*=10;
            x+=s[pos]-'0';
            pos++;
        }
    return x;
}
int mult()
{
    int res=fact();
    while(pos<s.size() && (s[pos]=='*' || s[pos]=='/'))
    {
        if(s[pos]=='*')
        {
            ++pos;
            res*=fact();
        }
        else
        {
            ++pos;
            res/=fact();
        }
    }
    return res;
}

int add()
{
    int res=mult();
    while(pos<s.size() && (s[pos]=='+' || s[pos]=='-'))
    {
        if(s[pos]=='+')
        {
            ++pos;
            res+=mult();
        }
        else
        {
            ++pos;
            res-=mult();
        }
    }
    return res;
}

int main()
{
    f>>s;
    g<<add();
    return 0;
}