#include <bits/stdc++.h>

using namespace std;
using tpl = tuple<int, int, int>;

const int N = 2e5 + 10, M = 4e3 + 10, W = 2e3;

int n, x[N], y[N], m, z[N], w[N], tr[M], ans[N];
vector<int> p[M];
vector<tpl> que[M][2];

inline int lowbit(int x) {
    return x & (-x);
}

void add(int x) {
    while (x < M) tr[x]++, x += lowbit(x);
}

int query(int x) {
    int ret = 0;
    while (x > 0) ret += tr[x], x -= lowbit(x);
    return ret;
}

bool Check(int d) {
    fill(tr, tr + M, 0);
    for (int i = 1; i <= n; i++) p[x[i]].push_back(y[i]);
    for (int i = 1; i <= m; i++) {
        que[max(0, z[i] - d)][0].push_back({max(0, w[i] - d), min(M - 1, w[i] + d), i});
        que[min(M - 1, z[i] + d)][1].push_back({max(0, w[i] - d), min(M - 1, w[i] + d), i});
        ans[i] = 0;
    }
    for (int i = 0; i < M; i++) {
        for (auto [l, r, id] : que[i][0]) {
            ans[id] -= query(r) - query(l - 1);
        }
        for (int k : p[i]) add(k);
        for (auto [l, r, id] : que[i][1]) {
            ans[id] += query(r) - query(l - 1);
        }
        que[i][0].clear(), que[i][1].clear(), p[i].clear();
    }
    for (int i = 1; i <= m; i++) if (ans[i] > 0) return 0;

    fill(tr, tr + M, 0);
    for (int i = 1; i <= m; i++) p[z[i]].push_back(w[i]);
    for (int i = 1; i <= n; i++) {
        que[max(0, x[i] - d)][0].push_back({max(0, y[i] - d), min(M - 1, y[i] + d), i});
        que[min(M - 1, x[i] + d)][1].push_back({max(0, y[i] - d), min(M - 1, y[i] + d), i});
        ans[i] = 0;
    }
    for (int i = 0; i < M; i++) {
        for (auto [l, r, id] : que[i][0]) {
            ans[id] -= query(r) - query(l - 1);
        }
        for (int k : p[i]) add(k);
        for (auto [l, r, id] : que[i][1]) {
            ans[id] += query(r) - query(l - 1);
        }
        que[i][0].clear(), que[i][1].clear(), p[i].clear();
    }
    for (int i = 1; i <= n; i++) if (ans[i] > 0) return 0;
    return 1;
}

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> x[i] >> y[i];
        int t = y[i];
        y[i] = x[i] - y[i], x[i] += t;
        x[i] += W, y[i] += W;
    }
    cin >> m;
    for (int i = 1; i <= n; i++) {
        cin >> z[i] >> w[i];
        int t = w[i];
        w[i] = z[i] - w[i], z[i] += t;
        z[i] += W, w[i] += W;
    }
    int l = 0, r = 2e3;
    while (l < r) {
        int mid = (l + r) >> 1;
        Check(mid) ? l = mid + 1 : r = mid;
    }
    cout << l;
    return 0;
}
//////