#include <bits/stdc++.h>
using namespace std;

const int N = 1e6 + 3;

int n, k, ans = 2e9;

vector <int> g[N], p[N], q[N], u(N, -1);

void f(int v, int x, int cnt, vector <int> l, vector <int> r) {
    u[v] = x;
    for (int j = 0; j < k; ++j) {
        l[j] = max(l[j], p[v][j]);
        r[j] = min(r[j], q[v][j]);
        if (l[j] > r[j]) {
            ans = min(ans, cnt);
            break;
        }
    }
    for (auto i : g[v])
        if (u[i] - x)
            f(i, x, cnt + 1, l, r);
}

int main() {
    freopen("input.txt", "r", stdin);
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    cin >> n >> k;
    for (int i = 0; i < n; ++i) {
        int x;
        for (int j = 0; j < k; ++j) {
            cin >> x;
            p[i].push_back(x);
        }
        for (int j = 0; j < k; ++j) {
            cin >> x;
            q[i].push_back(x);
        }
    }
    for (int i = 1; i < n; ++i) {
        int u, v;
        cin >> u >> v;
        g[--u].push_back(--v);
        g[v].push_back(u);
    }
    for (int i = 0; i < n; ++i)
        f(i, i, 0, p[i], q[i]);
    cout << (ans - 2e9 ? ans : -1);

    return 0;
}