Cod sursa(job #1118328)

Utilizator c0rn1Goran Cornel c0rn1 Data 24 februarie 2014 10:15:05
Problema Evaluarea unei expresii Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.17 kb
#include <iostream>
#include <fstream>
#include <string.h>

using namespace std;

ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
char s[100001];
int i;
int termen();
int factor();

int expresie()
{
    int v=termen();
    while(s[i]=='+' || s[i]=='-')
    {
        switch(s[i])
        {
            case '+':
                i++;
                v+=termen();
                break;
            case '-':
                i++;
                v-=termen();
                break;
        }
    }
    return v;
}

int termen()
{
    int v=factor();
    while(s[i]=='*' || s[i]=='/')
    {
        switch(s[i])
        {
            case '*':
                i++;
                v*=factor();
                break;
            case '/':
                i++;
                v/=factor();
                break;
        }
    }
    return v;
}

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

int main()
{
    fin.getline(s, 100001);
    fout<<expresie();
    return 0;
}