/*
* Author: Xiangmy
* Created: 2024-03-21 16:28
* Problem: 
* Description: 
*/
// #pragma GCC optimize(2)
// #pragma GCC optimize(3, "Ofast", "inline")
#include<bits/stdc++.h>
using namespace std;
#define debug(x) cerr << #x << ": " << (x) << ' '
// #define x first
// #define y second
typedef long long LL;
const int INF = 0x3f3f3f3f;
typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;

void solve() {
    LL n, m, x, y; cin >> n >> m >> x >> y;

    LL st = -1, ed = -1;
    vector<PLL> atob;
    for (int i = 1; i <= x; ++ i) {
        int a, b; cin >> a >> b;
        atob.push_back({a, b});
    }
    sort(atob.begin(), atob.end());
    vector<PLL> nowa;
    for (int i = 0; i < x; ++ i) {
        if (atob[i].first <= ed + 1) {
            ed = max(ed, atob[i].second);
        } else {
            if (ed - st + 1 >= m) {
                nowa.push_back({st, ed});
            }
            st = atob[i].first, ed = atob[i].second;
        }
    }
    if (ed - st + 1 >= m) {
        nowa.push_back({st, ed});
    }

    st = -1, ed = -1;
    vector<PLL> btoa;
    for (int i = 1; i <= y; ++ i) {
        int a, b; cin >> a >> b;
        btoa.push_back({a, b});
    }
    sort(btoa.begin(), btoa.end());
    vector<PLL> nowb;
    for (int i = 0; i < y; ++ i) {
        if (btoa[i].first <= ed + 1) {
            ed = max(ed, btoa[i].second);
        } else {
            if (ed - st + 1 >= m) {
                nowb.push_back({st, ed});
            }
            st = btoa[i].first, ed = btoa[i].second;
        }
    }
    if (ed - st + 1 >= m) {
        nowb.push_back({st, ed});
    }

    LL ans = 0;
    for (int i = 0, j = 0; i < nowa.size() && j < nowb.size(); ) {
        int af = nowa[i].first, as = nowa[i].second;
        int bf = nowb[j].first, bs = nowb[j].second;
        if (af <= bf) {
            if (as >= bs) {
                ans += max(0ll, bs - bf + 1 - (m - 1));
                j ++;
            } else if (bs > as) {
                ans += max(0ll, as - bf + 1 - (m - 1));
                i ++;
            } else {
                i ++;
            }
        } else if (af > bf) {
            if (as >= bs) {
                ans += max(0ll, bs - af + 1 - (m - 1));
                j ++;
            } else if (bs > as) {
                ans += max(0ll, as - af + 1 - (m - 1));
                i ++;
            } else {
                j ++;
            }
        }
    } 
    cout << ans << "\n";
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);  // 交互题不用
    cout.tie(0);
    // cout << fixed << setprecision(6);
    // cout << setw(4) << setfill('0');
    // init();
    int T = 1;
    cin >> T;
    while (T -- ) {
        // cin.ignore(numeric_limits<std::streamsize>::max(), '\n');
        solve();
    }
    return 0;
}