bfi

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

void execCode(string progCode, unsigned char *p);

int main(int argc, char **argv)
{
    fstream Code;
    string progCode = "", loadBuff;
    unsigned char progMem[30000];
    unsigned char *p;
    int i;
    if (argc==1)
    {
        cout << "usage: " << argv[0] << " filename.bf" << endl;
        return 1;
    }
    else
    {
        Code.open(argv[1], ios::in);
        if (Code.good() == true)
        {
            while (!Code.eof())
            {
                getline(Code, loadBuff);
                progCode = progCode + loadBuff;
                loadBuff = "";
            }
            Code.close();
        }
        else
        {
            cout << "cannot open " << argv[1]  << endl;
            return 2;
        }
        for (i=0; i<30000; i++)
        {
            progMem[i]=0;
        }
        p = &progMem[0];
        execCode(progCode, p);
    }
}

void execCode(string progCode, unsigned char *p)
{
    unsigned int i = 0;
    unsigned int loopCount = 0;
    char currentInstruction;
    for (i=0; progCode[i]!=0; i++)
    {
        currentInstruction=progCode[i];
        switch(currentInstruction)
        {
            case '>':
                ++p;
                break;
            case '<':
                --p;
                break;
            case '+':
                ++(*p);
                break;
            case '-':
                --(*p);
                break;
            case '.':
                cout << *p;
                break;
            case ',':
                cin >> *p;
                break;
            case '[':
                continue;
                break;
        }
        if (currentInstruction == ']' && *p)
        {
            loopCount = 1;
            while (loopCount > 0)
            {
                currentInstruction = progCode[--i];
                if (currentInstruction == '[')
                {
                    loopCount--;
                }
                else if (currentInstruction == ']')
                {
                    loopCount++;
                }
            }
        }
    }
}