#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
//using namespace __gnu_pbds;

// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2")
#define watch(x) cout<<(#x)<<"="<<(x)<<'\n'
#define mset(d,val) memset(d,val,sizeof(d))
#define cbug if(DEBUG) cout
#define setp(x) cout<<fixed<<setprecision(x)
#define sz(x) (int)(x).size()
#define all(x) begin(x), end(x)
#define forn(i,a,b) for(int i=(a);i<(b);i++)
#define fore(i,a,b) for(int i=(a);i<=(b);i++)
#define pb push_back
#define F first
#define S second
#define fbo find_by_order
#define ook order_of_key
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> ii;
typedef vector<ll> vi;
typedef vector<ii> vii;
//template<typename T>
//using pbds = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
void SD(int t=0){ cout<<"PASSED "<<t<<endl; }
ostream& operator<<(ostream &out, ii x){ out<<"("<<x.F<<","<<x.S<<")"; return out; }
template<typename T> void amax(T &a, T b){ a=max(a,b); }
template<typename T> void amin(T &a, T b){ a=min(a,b); }
struct Hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }
    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

const ll INF = ll(1e18);
const int MOD = 998244353;
const bool DEBUG = 0;
const int MAXN = 100005;
const int LG = 21;

ll add(ll a, ll b, ll m = MOD)
{
    a+=b;
    if(abs(a)>=m) a%=m;
    if(a<0) a+=m;
    return a;
}

ii operator+(const ii& a, const ii& b) { return {add(a.F, b.F), a.S + b.S}; }
ii& operator+=(ii& a, const ii& b) {
    a.F = add(a.F, b.F);
    a.S += b.S;
    return a;
}

struct Node
{
    ii val{0, 0};  // (val, cnt)
    int l = 0, r = 0;
};

vector<ll> dis;
vector<int> ans;

class PersistSegmentTree
{
private:
    int update(int pos, ii val, int k, int l, int r) {
        int k1 = createNode();
        v[k1] = v[k];
        if (l == r) {
            v[k1].val += val;
            return k1;
        }
        int mid = (l + r) >> 1;
        int cl = v[k1].l;
        int cr = v[k1].r;
        if (pos <= mid) {
            cl = v[k1].l = update(pos, val, cl, l, mid);
        } else {
            cr = v[k1].r = update(pos, val, cr, mid + 1, r);
        }
        v[k1].val = v[cl].val + v[cr].val;
        return k1;
    }
    bool le(int k1, int k2, int l, int r) {
        if (l == r) return v[k1].val.S <= v[k2].val.S;
        if (v[k1].val == v[k2].val) return true;
        int mid = (l + r) >> 1;
        if (v[k1 * 2 + 1].val != v[k2 * 2 + 1].val) return le(k1 * 2, k2 * 2, l, mid);
        return le(k1 * 2 + 1, k2 * 2 + 1, mid + 1, r);
    }
    void dfs(int k, int l, int r) {
        // assert(k >= 0);
        if (v[k].val.S == 0) return;
        // assert(k >= 1);
        if (l == r) {
            forn(i, 0, v[k].val.S) ans.pb(dis[l]);
            return;
        }
        int mid = (l + r) >> 1;
        dfs(v[k].r, mid + 1, r);
        dfs(v[k].l, l, mid);
    }
    // Node query(int s, int e, int k, int l, int r) {
    // 	if (r < l) return kInvalid;
    // 	if (s <= l && r <= e) return v[k].val;
    // 	int mid = (l + r) >> 1;
    // 	Node cl = query(s, e, k * 2, l, mid);
    // 	Node cr = query(s, e, k * 2 + 1, mid + 1, r);
    // 	return merge(cl, cr);
    // }

public:
    static constexpr ii kDefault = {0, 0};
    static constexpr ii kInvalid = {0, 0};
    int siz;
    vector<Node> v;
    PersistSegmentTree(int n) : siz(1), v(2, {kInvalid}) {
        while (siz < n) siz <<= 1;
    }
    int createNode() {
        v.push_back({{0, 0}, 0, 0});
        return sz(v) - 1;
    }
    int update(int pos, ii val, int k) {
        return update(pos, val, k, 0, siz - 1);
    }
    bool le(int k1, int k2) {
        return le(k1, k2, 0, siz - 1);
    }
    void dfs(int k) {
        return dfs(k, 0, siz - 1);
    }
    // ii query(int l, int r, int node) {
    // 	return query(l, r, node, 0, siz - 1);
    // }
};

mt19937 rng(727);

vector<ll> randVal(int n)
{
    unordered_set<ll> s;
    uniform_int_distribution<ll> dis(0, MOD - 1);
    forn(i,0,n)
    {
        int x = dis(rng);
        while (s.count(x)) x = dis(rng);
        s.insert(x);
    }
    return vector<ll>(all(s));
}

int compress(vector<ll>& v)
{
    set<ll> s(all(v));
    dis = vector<ll>(all(s));
    unordered_map<ll, ll, Hash> mp;
    forn(i,0,sz(dis)) mp[dis[i]] = i;
    forn(i,0,sz(v)) v[i] = mp[v[i]];
    return sz(dis);
}

void solve()
{
    int n; cin>>n;
    ll L, R; cin >> L >> R;
    vector<ll> x(n), a(n);
    forn(i,0,n) cin >> x[i];
    forn(i,0,n) cin >> a[i];
    vector<ll> a0(a);
    int m = compress(a);

    vector<ll> val = randVal(n);
    int l = 0, r = 0;
    PersistSegmentTree st(m);
    vector<int> roots;
    roots.reserve(n);
    deque<int> dq;
    int rt0 = st.update(a[0], {val[0], 1}, 1);
    dq.push_back(rt0);
    roots.pb(rt0);
    forn(i,1,n)
    {
        while (r < n && x[r] <= x[i] - L)
        {
            if (roots[r] != -1)
            {
                while (!dq.empty() && st.le(dq.back(), roots[r])) dq.pop_back();
                dq.push_back(roots[r]);
            }
            r++;
        }
        while (l < n && x[l] < x[i] - R)
        {
            if (!dq.empty() && roots[l] == dq.front()) dq.pop_front();
            l++;
        }
        int prt = -1;
        if (!dq.empty()) prt = dq.front();
        int k = prt == -1 ? -1 : st.update(a[i], {val[i], 1}, prt);
        roots.pb(k);
    }

    if (roots.back() != -1) st.dfs(roots.back());
    if (ans.empty())
    {
        cout << -1 << '\n';
        return;
    }
    cout << sz(ans) << '\n';
    for (const auto x : ans) cout<<x<<" ";
    cout << '\n';
    ans.clear();
}

int main()
{
    cin.tie(0)->sync_with_stdio(0);

    int t; cin>>t;
    fore(i,1,t) solve();

    return 0;
}