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

int xi[50005] , yi[500005], a,b,x,y,n,maxim,maxim1,minim,minim1,i,s;


int main () {
	
	fin>>n>>x>>y;
	for (i=1;i<=n;i++) {
		fin>>a>>b; 
		if (a>maxim) 
			maxim=a;
		if (b>maxim1) 
			maxim1=b;
		xi[a]++;
		yi[b]++;
	}
	
	for (i=1;i<=maxim;i++) 
		xi[i]=xi[i-1]+xi[i];
	
	for (i=1;i<=maxim1;i++)
		yi[i]=yi[i-1]+yi[i];
		
	minim=200000000;
	for (i=x-1;i<=maxim;i++) {
		s=xi[i-x+1]+xi[maxim]-xi[i];
		if (s<minim)
		minim=s;
	}
	
	minim1=20000000;
	
	for (i=y-1;i<=maxim1;i++) {
		s=yi[i-y+1]+yi[maxim1]-yi[i];
		if (s<minim1)
			minim1=s;
	}
	
	fout<<minim+minim1<<"\n";
	
	return 0; 
}