#include <bits/stdc++.h>
#define ll long long
#define F first
#define S second
#define endl '\n'
#define Endl '\n'

using namespace std;

const int N = 2e5 + 5;
int tc, n, m, a[N], b[N], c[N];
ll dp[N][3];
bool vis[N][3];

ll rec(int idx, int pre) {
    if (idx == n) {
        return 0;
    }
    ll &ret = dp[idx][pre];
    if (vis[idx][pre]) {
        return ret;
    }
    vis[idx][pre] = true;
    ret = INT_MIN;
    if (pre != 0) {
        ret = max(ret, a[idx] + rec(idx + 1, 0));
    }
    if (pre != 1) {
        ret = max(ret, b[idx] + rec(idx + 1, 1));
    }
    if (pre != 2) {
        ret = max(ret, c[idx] + rec(idx + 1, 2));
    }
    return ret;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); // cout.tie(0);
    cin >> tc;
    while (tc--) {
        cin >> n;
        for (int i = 0; i < n; i++) {
            cin >> a[i];
        }
        for (int i = 0; i < n; i++) {
            cin >> b[i];
        }
        for (int i = 0; i < n; i++) {
            cin >> c[i];
        }
        memset(vis, false, sizeof vis);
        cout << rec(0, -1) << endl;
    }

    return 0;
}