#include <bits/stdc++.h>
using namespace std;
 
#define fast_io ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define int long long
#define rep(i,a,b) for(int i=a;i<b;++i)
 
void solve() {
    int n;
    cin >> n;
    vector<int> a(n), b(n);
    rep(i,0,n) cin >> a[i];
    rep(i,0,n) cin >> b[i];
 
    int mx = 0, mn = 0;
    rep(i,0,n) {
        int new_mx = max(mx - a[i], b[i] - mn);
        int new_mn = min(mn - a[i], b[i] - mx);
        mx = new_mx;
        mn = new_mn;
    }
    cout << mx << '\n';
}
 
int32_t main() {
    fast_io;
    int t;
    cin >> t;
    while (t--) solve();
    return 0;
}
 

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3
3
4 -8 -1
-3 -7 0
5
-3 1 0 7 1
-5 3 -1 4 -5
5
-7 7 5 4 9
-9 -3 3 2 2