#include <iostream>
#include <fstream>

using namespace std;

const int nmax = 50006;
const char iname[] = "tribute.in";
const char oname[] = "tribute.out";

ifstream fin(iname);
ofstream fout(oname);

int n, dx, dy, i, x[nmax], y[nmax], ans;

int main()
{
	fin >> n >> dx >> dy;
	for(i = 1; i <= n; i ++)
		fin >> x[i] >> y[i];
	sort(x + 1, x + n + 1);
	sort(y + 1, y + n + 1);
	
	int lf = 1, rf = n;
	while(lf <= rf)
	{
		int ansx = x[rf] - x[lf] - dx;
		if(ansx > 0)
			ans += ansx;
		int ansy = y[rf] - y[lf] - dy;
		if(ansy > 0)
			ans += ansy;
		lf++;
		rf--;
	}
	
	fout << ans << "\n";
	return 0;
}