Cod sursa(job #3170357)

Utilizator MilitaruMihaiMihaiMIlitaru MilitaruMihai Data 17 noiembrie 2023 14:47:27
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.86 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
int expr();
int termen();
int factor();
int p;
char s[100005];
int expr()
{
    int r=termen();
    while (s[p]=='+' || s[p]=='-')
    {
        if (s[p]=='+') p++,r+=termen();
        else p++,r-=termen();
    }
    return r;
}
int termen()
{
    int r=factor();
    while (s[p]=='*' || s[p]=='/')
    {
        if (s[p]=='*') p++,r*=factor();
        else p++,r/=factor();
    }
    return r;
}
int factor()
{
    int r=0;
    if (s[p]=='(')
    {
        p++;
        r=expr();
        p++;
    }
    else
    {
        while (s[p]>='0' && s[p]<='9')
        {
            r=r*10+s[p]-'0';
            p++;
        }
    }
    return r;
}
int main()
{
    fin>>s;
    fout<<expr();
    return 0;
}