#include <bits/stdc++.h>
#define fi first
#define se second
#define PB push_back
#define EB emplace_back
using namespace std;
typedef long long i64;
struct IO {
	char buf[1 << 23], *p1 = buf, *p2 = buf;
	char nc() { return p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 23, stdin), p1 == p2) ? EOF : *p1++; }
	template <typename T = int>
	T read() {
		char ch = nc();
		T sum = 0;
		while (ch < '0' || ch > '9') ch = nc();
		while (ch >= '0' && ch <= '9') sum = sum * 10 + ch - '0', ch = nc();
		return sum;
	}
} IO;
const int maxn = 1000000;
int w[maxn + 5], v[maxn + 5];
int nw[maxn + 5];
pair<int, int> mn[maxn + 5][20];
int lg2[maxn + 5];
inline int qMn(int l, int r) {
	if (l > r) return 0;
	int t = lg2[r - l + 1];
	return min(mn[l][t], mn[r - (1 << t) + 1][t]).se;
}
int main() {
	int T;
	scanf("%d", &T);
	while (T--) {
		int n = IO.read(); i64 S = IO.read<i64>();
		for (int i = 1; i <= n; i++) w[i] = IO.read();
		for (int i = 1; i <= n; i++) v[i] = IO.read();
		i64 t = max(S - 1000000, 0LL), sum = 0, c = 0;
		vector<pair<int, i64>> st;
		st.EB(0, 0);
		for (int i = 1; i <= n; i++)
			if (sum + w[i] <= t) {
				sum += w[i], c += v[i];
				st.EB(i, sum);
			}
		for (int i = n; i; i--) {
			mn[i][0] = {w[i], i};
			for (int j = 1; i + (1 << j) - 1 <= n; j++) mn[i][j] = min(mn[i][j - 1], mn[i + (1 << (j - 1))][j - 1]);
		}
		for (int i = 2; i <= n; i++) lg2[i] = lg2[i >> 1] + 1;
		memset(nw, 63, sizeof(nw));
		for (int i = 0; i < st.size(); i++) {
			int id = qMn(st[i].fi + 1, i == st.size() - 1 ? n : st[i + 1].fi - 1);
			if (id) nw[w[id] + st[i].se - t] = min(nw[w[id] + st[i].se - t], id);
		}
		i64 ans = c;
		i64 tt = t + 1;
		for (int i = 1; tt <= S; i++, tt++)
			if (nw[i] <= 1E6) {
				int id = nw[i];
				int lst = n;
				while (!st.empty() && st.back().fi > id) {
					int x = qMn(st.back().fi + 1, lst);
					if (x && nw[w[x] + st.back().se - t] == x) nw[w[x] + st.back().se - t] = 1E9;
					c -= v[st.back().fi];
					lst = st.back().fi - 1;
					st.pop_back(); 
				}
				int x = qMn(st.back().fi + 1, lst - 1);
				if (x && nw[w[x] + st.back().se - t] == x) nw[w[x] + st.back().se - t] = 1E9;
				c += v[id];
				x = qMn(st.back().fi + 1, id - 1);
				if (x) nw[w[x] + st.back().se - t] = min(nw[w[x] + st.back().se - t], x);
				st.EB(id, st.back().se + w[id]);
				x = qMn(id + 1, n);
				if (x) nw[w[x] + st.back().se - t] = min(nw[w[x] + st.back().se - t], x);
				ans = max(ans, c);
			}
		printf("%lld\n", ans);
	}
}