#include <bits/stdc++.h>
using namespace std;
#define int long long
#define arr array
#define vec vector
#define pii pair<int, int>
#define fir first
#define sec second
const int N = 3e5 + 5, INF = 1e18;
int n;
arr<int, N> vl, cst;
arr<vec<int>, N> adj;
arr<vec<pii>, N> trns;
arr<int, N> mn;
void prcmp() {
vec<pii> cls = {{-1, 1}};
for (int u = 1; u <= n; u++) {
if (u != 1 && vl[u - 1] + 1 != vl[u]) {
if (vl[u] == 0) {
int cl = vl[u - 1] + 1;
if (cls.size() && cls.back().fir == cl) cls.back().sec = u;
else cls.push_back({cl, u});
} else {
cls.clear();
cls.push_back({-1, u});
}
}
if (cls.size() >= 2 && cls.back().fir >= vl[u] + 1)
trns[u].push_back({cls.back().fir, cls[cls.size() - 2].sec});
trns[u].push_back({-1, cls.back().sec});
}
mn[n + 1] = INF;
for (int c = n; c >= 1; c--) mn[c] = min(mn[c + 1], cst[c]);
}
arr<int, N> dp;
void cmp() {
for (int u = 1; u <= n; u++) {
dp[u] = INF;
assert(trns[u].size()<=1);
for (pii x : trns[u]) {
int nw_dp = dp[x.sec - 1] + ((x.fir == -1) ? mn[vl[u] + 1] : cst[x.fir]);
dp[u] = min(dp[u], nw_dp);
}
}
cout << dp[n] << endl;
}
signed main() {
cin >> n;
for (int u = 1; u <= n; u++) cin >> vl[u];
for (int c = 1; c <= n; c++) cin >> cst[c];
for (int i = 1; i < n; i++) {
int u, v; cin >> u >> v;
adj[u].push_back(v), adj[v].push_back(u);
}
prcmp();
cmp();
}
