/* Problem URL: https://codeforces.com/contest/2037/problem/D */

#include <bits/stdc++.h>

using namespace std;

#define V vector

#define rmin(a, b) a = min(a, b)
#define rmax(a, b) a = max(a, b)

#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)

#define repv(i, v) for (auto &i : (v))
#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
#define sortv(v) sort(v.begin(), v.end())
#define all(v) (v).begin(), (v).end()

using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vvvvi = vector<vvvi>;

using ll = long long;

using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vvvvl = vector<vvvl>;

template<class v>
auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
    os << vec[0];
    for (size_t i = 1; i < vec.size(); i++) {
        os << ' ' << vec[i];
    }
    os << '\n';
    return os;
}

template<class v>
auto operator>>(istream &is, vector<v> &vec)->istream& {
    for (auto &i : vec) {
        is >> i;
    }
    return is;
}

template<class v>
auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
    for (auto &i : vec) {
        os << i[0];
        for (size_t j = 1; j < i.size(); j++) {
            os << ' ' << i[j];
        }
        os << '\n';
    }
    return os;
}

template<class v>
auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
    for (auto &i : vec) {
        for (auto &j : i) {
            is >> j;
        }
    }
    return is;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t;
    cin >> t;

    while (t--) {
        ll n, m, l;
        cin >> n >> m >> l;

        V<pair<ll, ll>> hurd(n);
        for (auto &[l, r] : hurd) {
            cin >> l >> r;
        }

        V<pair<ll, ll>> p(m);
        for (auto &[l, r] : p) {
            cin >> l >> r;
        }

        int ans = 0;
        ll k = 1;

        size_t i = 0;
        size_t j = 0;
        priority_queue<ll> pq;

        while (i < hurd.size()) {
            while (j < p.size() && p[j].first <= hurd[i].first) {
                pq.push(p[j].second);
                j++;
            }

            while (!pq.empty() && hurd[i].second - hurd[i].first + 1 >= k) {
                k += pq.top();
                pq.pop();
                ans++;
            }

            if (hurd[i].second - hurd[i].first + 1 >= k) {
                break;
            }
            i++;
        }

        if (i < hurd.size()) {
            cout << "-1\n";
            continue;
        }
        cout << ans << '\n';
    }
}