#include<fstream>
#define NMax 50005
using namespace std;
ifstream fin("tribute.in");
ofstream fout("tribute.out");

int N,DX,DY;
int X[NMax],Y[NMax];

void Read()
{
    fin>>N>>DX>>DY;

    for(int i=1;i<=N;++i)
    {
        int x,y;    fin>>x>>y;
        X[x]++;
        Y[y]++;
    }
}

int Sol(int V[], int D)
{
    int Smin=0,S=0;

    for (int i=D; i<NMax; ++i)
        S += ((i-D)*V[i]);

    Smin = S;

    for (int i=1; i<NMax; ++i)
        V[i] += V[i-1];

    for (int i=1; i+D<NMax; ++i)
    {
        S+=V[i-1];
        S-=(N-V[i+D-1]);
        Smin = min(Smin,S);
    }

    return Smin;
}

void Print()
{
    int x,y;
    x = Sol(X,DX);
    y = Sol(Y,DY);
    fout<<x+y<<"\n";
}

int main()
{
    Read();
    Print();

    fin.close();
    fout.close();
    return 0;
}