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

void chmax(int &x, int v) {
    if (x < v)
        x = v;
}

struct Segtree {
    vector<int> mx;
    int n;
    Segtree(int _n) : n(_n), mx(_n*2, -1e9) {}
    void edit(int p, int x) {
        p += n;
        for (mx[p] = max(mx[p], x); p > 1; p >>= 1) {
            mx[p >> 1] = max(mx[p], mx[p ^ 1]);
        }
    }
    int query(int l, int r) {
        int res = -1e9;
        for (l += n, r += n; l < r; l >>= 1, r >>= 1) {
            if (l & 1) res = max(res, mx[l++]);
            if (r & 1) res = max(res, mx[--r]);
        }
        return res;
    }
};

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int T;cin >> T;
    while (T--) {
        int n, m;
        cin >> n >> m;
        vector<int> a(n), b(m);
        for (int i = 0; i < n; i++) {
            cin >> a[i];
        }
        for (int i = 0; i < m; i++) {
            cin >> b[i];
        }

        vector<int> l1, l2, r1, r2;
        l1.push_back(0);
        l2.push_back(0);
        r1.push_back(n);
        r2.push_back(m);

        for (int i = 0; i < n; i++) {
            if (a[i] == 1) {
                l1.push_back(i + 1);
            }
        }
        for (int i = 0; i < m; i++) {
            if (b[i] == 1) {
                l2.push_back(i + 1);
            }
        }

        for (int i = n-1; i >= 0; i--) {
            if (a[i] == 3) {
                r1.push_back(i);
            }
        }
        for (int i = m-1; i >= 0; i--) {
            if (b[i] == 3) {
                r2.push_back(i);
            }
        }


        const int SL = min(l1.size(), l2.size());
        const int SR = min(r1.size(), r2.size());
        const int S = max(n, m);
        vector<int> preA(S + 1), preB(S + 1);
        vector<int> pre(S * 2 + 1, -1e9), suf(S * 2 + 1, -1e9);

        for (int i = 0; i < S; i++) {
            preA[i + 1] = preA[i] + (i < n && a[i] == 2);
        }
        for (int i = 0; i < S; i++) {
            preB[i + 1] = preB[i] + (i < m && b[i] == 2);
        }

        int ans = 0;
        Segtree sgt1(S * 2 + 1);
        Segtree sgt2(S * 2 + 1);

        const auto add = [&](int i) {
            int key = preA[l1[i]] - preB[l2[i]] + S;
            sgt1.edit(key, i - preA[l1[i]]);
            sgt2.edit(key, i - preB[l2[i]]);
        };
        int it = 0;
        for (int i = SR - 1; i >= 0; i--) {
            // cerr << "now " << r1[i]+1 << ' ' << r2[i] + 1 << endl;
            while (it < SL && l1[it] <= r1[i] && l2[it] <= r2[i]) {
                // cerr << "add " << l1[it]+1 << ' ' << l2[it]+1 << endl;
                add(it++);
            }
            int key = preA[r1[i]] - preB[r2[i]] + S;
            ans = max(ans, i + preA[r1[i]] + sgt1.query(key, S*2+1));
            ans = max(ans, i + preB[r2[i]] + sgt2.query(0, key));
        }
        cout << ans << '\n';

    }
    return 0;
}