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

inline int rd() {
	int x = 0;
	bool f = false;
	char c = getchar();
	for (; !isdigit(c); c = getchar()) f |= (c == '-');
	for (; isdigit(c); c = getchar()) x = x * 10 + (c ^ 48);
	return f ? -x : x;
}

#define fr     first
#define sc     second
#define pb     push_back
#define mp     make_pair
#define pii    pair<int, int>
#define all(x) (x).begin(), (x).end() 

#define N 200007

int pos[N];

pair<int, int> a[N];

ll p, q, sum[N];

vector<int> res;

inline bool check(int l, int r) {
	return (sum[r] - sum[l]) * p >= (r - l) * q * a[r].fr;
}

inline void work() {
	int n = rd();
	for (int i = 1; i <= n; ++i) {
		a[i].fr = rd(); a[i].sc = i;
	}
	sort(a + 1, a + 1 + n);
	for (int i = 1; i <= n; ++i) sum[i] = sum[i - 1] + a[i].fr;
	p = rd(), q = rd();
	int r = 1;
	while (r < n && check(0, r + 1)) ++r;
	pos[0] = r;
	int ans = n - r;
	for (int l = 1; l < n; ++l) {
		while (r < n && check(l, r + 1)) ++r;
		pos[l] = r;
		ans = min(ans, n - r + l);
	}
	int L = n, R = 0;
	for (int l = 0; l < n; ++l)
		if (n - pos[l] + l == ans) {
			L = min(L, l);
			R = max(R, pos[l]);
		}
	while (a[L].fr == a[L + 1].fr) --L;
	++R;
	while (a[R].fr == a[R - 1].fr) ++R;
	printf("%d\n", L + n - R + 1);
	res.clear();
	for (int i = 1; i <= L; ++i) res.pb(a[i].sc);
	for (int i = R; i <= n; ++i) res.pb(a[i].sc);
	sort(all(res));
	for (auto x : res) printf("%d ", x);
	puts("");
}

int main() {
	for (int t = rd(); t; --t) work();
	return 0;	
}