#include<bits/stdc++.h>

#pragma GCC target("avx2")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

using namespace std;

#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file(s) freopen(s".in", "r", stdin);freopen(s".out", "w", stdout);
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ft first
#define sd second
#define ll long long
#define pii pair<int,int>
#define pll pair<ll,ll>
const int N = 1e6 + 10;
const int M = 2e7 + 5;
const int B = 316;
const ll msize = 2;
const ll mod1 = 1e9 + 7;
const ll mod2 = 998244353;
const long double Phi = acos(-1);
const long long inf = 2e18;
const vector <pair<int, int>> dir = {{-1, 0}, {1, 0}, {0, -1}, {0, 1}};

ll binmul(ll x, ll ti, ll m);
ll binpow(ll x, ll ti, ll m);

ll n, m;
ll a[2005], b[2005];
vector <pll> projectors;

bool check(ll x, ll y) {
    vector <pll> v;
    for (int i = 1; i <= n; ++ i) {
        v.emplace_back(a[i] + x, b[i] + y);
    }
    sort(all(v));
    for (int i = 1; i < n; ++ i) v[i].sd = min(v[i].sd, v[i - 1].sd);

    int j = 0;
    for (int i = 0; i < m; ++ i) {
        while (j < n && v[j].ft <= projectors[i].ft) ++ j;
        -- j;

        if (j >= 0 && v[j].sd <= projectors[i].sd) return false;
    }

    return true;
}

ll f(ll x) {
    ll l = 0, r = 2e6, ans = 2e6;
    while (l <= r) {
        ll mid = (l + r) / 2;
        if (check(x, mid)) r = mid - 1, ans = mid;
        else l = mid + 1;
    }
    return ans + x;
}


const void solve() {
    cin >> n >> m;
    for (int i = 1; i <= n; ++ i) cin >> a[i] >> b[i];
    for (int i = 1; i <= m; ++ i) {
        ll x, y;
        cin >> x >> y;
        projectors.emplace_back(x, y);
    }
    sort(all(projectors));

    ll l = 0, r = 1e6;
    for (int i = 1; i <= 25; ++ i) {
        ll m1 = l + (r - l) / 3;
        ll m2 = r - (r - l) / 3;

        if (f(m1) <= f(m2)) r = m2;
        else l = m1;
    }

    ll ans = inf;
    for (int i = l; i <= r; ++ i) ans = min(ans, f(i));
    cout << ans;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    srand(time(NULL));

    // file("maze");

    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);

    int tt = 1;
    // cin >> tt;
    for (int i = 1; i <= tt; ++ i) {
        solve();
    }

    #ifndef ONLINE_JUDGE
        cerr << "\n" << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
    #endif

    return 0;
}


// Template functions
ll binmul(ll x, ll ti, ll m) { ll res = 0;while (ti){if(ti & 1)res += x;x += x;ti >>= 1; x %= m; res %= m;} return res;}
ll binpow(ll x, ll ti, ll m) { ll res = 1;while (ti){if(ti & 1)(res *= x)%=m;(x*=x)%=m;ti >>= 1; x %= m; res %= m;} return res;}