#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 lastTaken) {
if (idx == n) {
return 0;
}
ll &ret = dp[idx][lastTaken];
if (vis[idx][lastTaken]) {
return ret;
}
vis[idx][lastTaken] = true;
ret = 0;
if (lastTaken != 0) {
ret = max(ret, a[idx] + rec(idx + 1, 0));
}
if (lastTaken != 1) {
ret = max(ret, b[idx] + rec(idx + 1, 1));
}
if (lastTaken != 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, 0, sizeof vis);
cout << rec(0, -1) << endl;
}
return 0;
}