#include<bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define endl '\n'
#define ll long long
#define pb push_back
#define yes cout<<"YES\n"
#define no cout<<"NO\n"
#define noo cout<<"-1\n"
#define vi vector<int>
#define vl vector<long long>

#define int long long

typedef pair<int,int>PII;

//const int N = 
//const int MOD = 


void solve()
{
	int leng,k,n,m;cin>>leng>>k>>n>>m;
	vector<PII>a(n),b(m);
	for(auto &t:a)
		cin>>t.fi>>t.se;
	for(auto &t:b)
		cin>>t.fi>>t.se;
	sort(a.begin(),a.end());
	sort(b.begin(),b.end());
	int res=0,j=0;
	for(int i=0;i<m;i++)
	{
		int s=0;
		while(j<n&&a[j].se<=b[i].se)
		{
			int t=a[j].se-max(a[j].fi,b[i].fi)+1;
			res+=max(0ll,t-k+1);
			j++;
			//cout<<res<<endl;
		}
		if(j<n&&b[i].se<a[j].se)
		{
			int t=b[i].se-max(a[j].fi,b[i].fi)+1;
			//cout<<b[i].se<<' '<<a[j].se<<endl;
			res+=max(0ll,t-k+1);
			//cout<<t<<endl;
		}
		 //cout<<res<<endl;
	}
	cout<<res<<endl;
}

signed main()
{
	ios_base::sync_with_stdio(0);
	int T=1;
	cin>>T;
	while(T--)solve();
	return 0;
}