#include <bits/stdc++.h>

using namespace std;
ifstream r("tribute.in");
ofstream w("tribute.out");
int l[50002], c[50002];
int main()
{
    int n, a, b;
    r>>n>>a>>b;
    for(int i=0;i<n;i++){
        r>>l[i]>>c[i];
    }
    sort(l, l+n);
    sort(c, c+n);
    int sum=0;
    for(int i=0;i<n/2;i++){
        sum+=max(l[n-i-1]-l[i]-a, 0);
        sum+=max(c[n-i-1]-c[i]-b, 0);
    }
    w<<sum;
    return 0;
}