#include <bits/stdc++.h>

using namespace std;

const int N = 50000;
int x[5 + N];
int y[5 + N];

int main()
{
    freopen("tribute.in", "r", stdin);
    freopen("tribute.out", "w", stdout);
    int n, dx, dy, i, sol = 0;
    scanf("%d%d%d", &n, &dx, &dy);
    for(i = 1; i <= n; i++) scanf("%d%d", &x[i], &y[i]);
    sort(x + 1, x + n + 1);
    sort(y + 1, y + n + 1);
    for(i = 1; i <= n; i++){
        sol += max(0, x[i + 1] - x[n - i] - dx);
        sol += max(0, y[i + 1] - y[n - i] - dy);
    }
    printf("%d\n", sol);
    return 0;
}