#include<bits/stdc++.h>
using namespace std;
const int N=5010;
int n,a,b;
int la[N],ra[N],lb[N],rb[N];
int f[N][N];
set<int>s[N];
void solve(int l,int r,int id){
	set<int>::iterator it=s[id].lower_bound(l);
	vector<int>ve;
	for(;it!=s[id].end()&&(*it)<=r;it++){
		int x=*it;ve.push_back(x+1);
		f[id][x+1]=f[id+1][x]=1;
		s[id+1].insert(x);
	}
	while(1){
		it=s[id].lower_bound(l);
		if(it==s[id].end())break;
		if((*it)>r)break;
		s[id].erase(*it);
	}
	for(int x:ve)s[id].insert(x);
}
int main(){
	scanf("%d%d%d",&n,&a,&b);
	for(int i=1;i<=n;i++){
		scanf("%d%d%d%d",&la[i],&ra[i],&lb[i],&rb[i]);
		la[i]-=a,ra[i]-=a,lb[i]-=b,rb[i]-=b;
		la[i]=max(la[i],0),ra[i]=max(ra[i],0);
		lb[i]=max(lb[i],0),rb[i]=max(rb[i],0);
		la[i]=min(la[i],n),ra[i]=min(ra[i],n);
		lb[i]=min(lb[i],n),rb[i]=min(rb[i],n);
	}
	f[0][0]=1;s[0].insert(0);
	for(int t=1;t<=n;t++){
		for(int i=la[i];i<=ra[i];i++){
			solve(lb[i],rb[i],i);
		}
		// for(int i=0;i<=n;i++){
			// for(int j=0;j<=n;j++){
				// cout<<f[i][j]<<" ";
			// }
			// cout<<endl;
		// }
		// cout<<endl;
	}
	int ans=0;
	for(int i=0;i<=n;i++){
		for(int j=0;j<=n;j++){
			if(f[i][j])ans=max(ans,i+j);
		}
	}
	cout<<ans;
	return 0;
}