Cod sursa(job #2812385)

Utilizator MrPuzzleDespa Fabian Stefan MrPuzzle Data 4 decembrie 2021 14:35:22
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.22 kb
#include<fstream>
#include<iostream>
#include<climits>
#include<algorithm>
#include<cstring>
#include<cmath>
using namespace std;

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

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

int expresie();
int termen();
int factor();

char s[100003];
int i=0;

int main()
{
    f>>s;
    g<<expresie();
    f.close();
    g.close();
    return 0;
}

int expresie()
{
    int r=termen();
    while(s[i]=='+'||s[i]=='-')
    {
        if(s[i]=='+')
        {
            i++;
            r+=termen();
        }
        else
        {
            i++;
            r-=termen();
        }
    }
    return r;
}

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

int factor()
{
    int r=0;

    if(s[i]=='(')
    {
        i++;
        r=expresie();
        i++;
    }
    else
    {
        while(s[i]>='0'&&s[i]<='9')
        {
            r=r*10+(s[i]-'0');
            i++;
        }
    }

    return r;
}