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

using std::string;
using std::endl;
using std::cout;
using std::cerr;


int main(int argc, char const *argv[])
{
	if (argc < 4) {
        cerr << "Error, wrong format. Try prog.exe read/write filename \"data\"" << endl;
        return -1;
    }

	if (string(argv[1]) == "read") {
        std::ifstream inFile;
        inFile.open(string(argv[2]));

        if (!inFile.is_open()) {
            cerr << "Error: Cannot open " << argv[2] << endl;
            return -1;
        }

        string line;
        while(std::getline(inFile, line))
            cout << line << endl;

        inFile.close();
    }
    else if (string(argv[1]) == "write") {
        std::ofstream outFile(string(argv[2]), std::ios::app);

        if (!outFile.is_open()) {
            cerr << "Error: Cannot open " << argv[2] << endl;
            return -1;
        }

        outFile << argv[3] << endl;
        outFile.close();
    }
    else
        cerr << "Wrong format, try read/write" << endl;

    return 0;
}