Part 1 of Day 8 of Advent of Code. The reason for it being a whole new class called Day8 is that I use a single main.cpp to run each day's code, just instantiating a Day6, 7, 8, etc... and using the run() method.

Day8.cpp

#include "stdafx.h"
#include "Day8.h"
#include <iostream>
#include <string>
#include <fstream>
#include <regex>

using namespace std;

// this is just to make my code later on cleaner and simpler, whereas up here I don't really care.
#define REG_REPLACE(str) regex_replace(regex_replace(regex_replace(regex_replace(str, memquotes, ""), doubleslash, "_"), asciihex, "_"), actualquotes, "_")

string &lines = string("");
string &memlines = string("");

regex memquotes("^\"|\"$");
regex doubleslash("\\\\\\\\");
regex asciihex("\\\\x[a-zA-Z0-9]{2}");
regex actualquotes("\\\\\"");

void Day8::run() {
	lines = "";
	memlines = "";

	cout << "Storing all lines... ";
	
	fstream file("Day 8 Input.txt");

	string line;

	while (getline(file, line)) {
		lines += REG_REPLACE(line);
		memlines += line;
	}

	cout << "DONE" << endl;
	cout << endl << "Done!" << endl;
	cout << "Length in memory: " << memlines.length() << endl;
	cout << "Actual length: " << lines.length() << endl;
	cout << "Difference: " << memlines.length() - lines.length() << endl;

	cin.get();
}