Cod sursa(job #1639789)

Utilizator KOzarmOvidiu Badea KOzarm Data 8 martie 2016 14:01:36
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.08 kb
#include <fstream>
#include <string.h>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
int i,k,n;
char x[100005];
int termen();
int factor();
int scoatenr()
{
    int nr=0;
    while(x[i]>='0'&&x[i]<='9')
    {
        nr=nr*10+x[i]-'0';
        i++;
    }
    return nr;
}
int eval()
{
    int a=termen();
    while(x[i]=='+'||x[i]=='-')
    {
        if(x[i]=='+')
        {
            i++;
            a+=termen();
        }
        else
        {
            i++;
            a-=termen();
        }
    }
    return a;
}
int termen()
{
    int a=factor();
    while(x[i]=='*'||x[i]=='/')
    {
        if(x[i]=='*')
        {
            i++;
            a*=factor();
        }
        else
        {
            i++;
            a/=factor();
        }
    }
    return a;
}
int factor()
{
    int a;
    if(x[i]=='(')
    {
        i++;
        a=eval();
        i++;
    }
    else
        a=scoatenr();
    return a;
}
int main()
{
    fin.getline(x,100005);
    fout<<eval();
    return 0;
}