#include <iostream>
#include <fstream>
#include <algorithm>

#define NMAX 50000

std::ifstream fin ( "tribute.in" );
std::ofstream fout ( "tribute.out" );

int l[1 + NMAX];
int c[1 + NMAX];

int main ( ) { 

	int N, DX, DY;

	fin >> N >> DX >> DY;

	for ( int i = 1; i <= N; ++i )
		fin >> l[i] >> c[i];

	std::sort ( l + 1, l + N + 1 );
	std::sort ( c + 1, c + N + 1 );

	int ans = 0;

	for ( int i = 1; i <= N / 2; ++i ) {
		ans += std::max ( l[N - i + 1] - l[i] - DX, 0 ); 
		ans += std::max ( c[N - i + 1] - c[i] - DY, 0 );
	}

	fout << ans << '\n';

	return 0;
}