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// 笛卡尔树，默认为大根堆
template <class T, typename Compare = std::greater<T>>
struct CartesianTree {
    T inf = std::numeric_limits<T>::max();

    struct Node {
        int idx;               // 原数组下标
        T val;                 // 权值
        int par, siz;          // 父节点索引，子树大小
        std::array<T, 2> son;  // 左儿子，右儿子

        Node(int idx = 0, T val = 0, int par = 0, int siz = 0) : idx(idx), val(val), par(par), siz(siz), son{} {}
    };

    std::vector<Node> t;

    CartesianTree() { init(); }

    void init(Compare comp = Compare()) {
        t.assign(1, {0, 0, 0});
        t[0].son.fill(0);
        if (comp(-inf, inf))
            t[0].val = -inf;
        else
            t[0].val = inf;
    }  // 自动建立虚拟节点

    void add(int idx, T val, int par = 0) { t.emplace_back(idx, val, par); }  // 负责把元素加进末尾，需要使用1-based

    int work(Compare comp = Compare()) {
        for (int i = 1; i < t.size(); i++) {
            int k = i - 1;
            while (comp(t[i].val, t[k].val)) k = t[k].par;
            t[i].son[0] = t[k].son[1];
            t[k].son[1] = i;
            t[i].par = k;
            t[t[i].son[0]].par = i;
        }  // 遍历，砍树枝
        auto dfs = [&](auto&& dfs, int u) -> void {
            if (!u) return;
            t[u].siz = 1;
            dfs(dfs, ls(u));
            dfs(dfs, rs(u));
            t[u].siz += t[ls(u)].siz + t[rs(u)].siz;
        };  // 进行一个dfs
        dfs(dfs, t[0].son[1]);
        return t[0].son[1];
    }

    int Left(int p) { return p - size(ls(p)); }  // 左边最远

    int Right(int p) { return p + size(rs(p)); }  // 右边最远

    int size(int p) { return t[p].siz; }

    int ls(int p) { return t[p].son[0]; }

    int rs(int p) { return t[p].son[1]; }

    int par(int p) { return t[p].par; }
};
/* 使用示例
CartesianTree<int, less<int>> ct;

rep(i, 0, n - 1) { ct.add(i + 1, nums[i]); }

int root = ct.work(less<int>());
rep(i, 1, n) {
    int L = ct.Left(i);
    int R = ct.Right(i);
}
*/
const ll MX = 1LL << 18;
ll las[MX];
ll tag[MX];
ll tim = 0;
void solve() {
    ll n;
    cin >> n;
    vl a(n);
    rep(i, 0, n - 1) cin >> a[i];
    vl pre(n + 1);
    rep(i, 1, n) pre[i] = pre[i - 1] ^ a[i - 1];
    CartesianTree<ll> ct;
    rep(i, 0, n - 1) ct.add(i + 1, a[i]);
    ct.work();
    vl l(n + 1), r(n + 1);
    vvl queries(n + 1);
    vector<bool> vis(n + 1, false);
    rep(i, 1, n) {
        l[i] = ct.Left(i), r[i] = ct.Right(i);
        if (i - l[i] + 1 <= r[i] - i + 1)
            queries[r[i]].emplace_back(i);
        else
            vis[i] = true;
    }
    auto check = [&](ll x) -> bool {
        tim++;
        vl pre2(n + 1);
        rep(i, 0, n) pre2[i] = (pre[i] & x);
        rep(i, 0, n) {
            tag[pre2[i]] = tim;
            las[pre2[i]] = i;
            for (auto& j : queries[i]) {
                if ((a[j - 1] & x) != x) continue;
                rep(v, l[j] - 1, j - 1) {
                    ll l1 = max(j, v + 2);
                    if (l1 > i) continue;
                    if (tag[pre2[v] ^ x] == tim && las[pre2[v] ^ x] >= l1) return true;
                }
            }
            if (i + 2 <= n && vis[i + 2] && ((a[i + 1] & x) == x)) {
                if (l[i + 2] - 1 <= i && tag[pre2[i + 2] ^ x] == tim && las[pre2[i + 2] ^ x] >= l[i + 2] - 1) return true;
            }
            if (i + 1 <= n && vis[i + 1] && ((a[i] & x) == x)) {
                rep(v, i + 2, r[i + 1]) {
                    if (l[i + 1] - 1 <= i && tag[pre2[v] ^ x] == tim && las[pre2[v] ^ x] >= l[i + 1] - 1) return true;
                }
            }
        }
        return false;
    };
    ll ans = 0;
    frep(i, 17, 0) {
        if (check(ans | (1LL << i))) ans = (ans | (1LL << i));
    }
    cout << ans << endl;
    return;
}

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struct Node {
    int a[3];
    ll b;
};
void solve() {
    ll n;
    cin >> n;
    vi a(n);
    rep(i, 0, n - 1) cin >> a[i], a[i]--;
    ll ans = (n - 1) * n / 2;
    stack<int> s;
    vi r(n, n);
    frep(i, n - 1, 0) {
        while (!s.empty() && a[s.top()] <= a[i]) s.pop();
        if (!s.empty()) r[i] = s.top();
        s.push(i);
    }
    vvi ma(n);
    rep(i, 0, n - 1) {
        if (r[i] != n) ma[r[i]].push_back(i);
    }
    vi siz(n);
    auto dfs = [&](this auto&& dfs, int x, int pa) -> void {
        siz[x] = 1;
        for (auto& p : ma[x]) {
            if (p == pa) continue;
            dfs(p, x);
            siz[x] += siz[p];
        }
        return;
    };
    rep(i, 0, n - 1) {
        if (r[i] == n) dfs(i, -1);
    }
    auto dfs2 = [&](this auto&& dfs2, int x, bool flag) -> Node {
        Node res = {{1, 0, 0}, 0};
        if (ma[x].empty()) return res;
        ll idx = ma[x][0];
        ll re = siz[x] - siz[idx] - 1;
        auto tem = dfs2(idx, flag);
        Node cur = {0, tem.a[0], tem.a[1], tem.b + siz[idx] - tem.a[0] - tem.a[1] - tem.a[2] + 3 * tem.a[2]};
        ans += (flag ? cur.a[1] + 2 * cur.a[2] + cur.b : cur.a[1] + 2 * cur.a[2] + 3 * (siz[idx] - cur.a[0] - cur.a[1] - cur.a[2]));
        Node cur2 = {0, cur.a[0], cur.a[1], cur.b + siz[idx] - cur.a[0] - cur.a[1] - cur.a[2] + 3 * cur.a[2]};
        ans += (flag ? cur2.a[1] + 2 * cur2.a[2] + cur2.b : cur2.a[1] + 2 * cur2.a[2] + 3 * (siz[idx] - cur2.a[0] - cur2.a[1] - cur2.a[2])) * re;
        rep(i, 0, 2) res.a[i] += cur.a[i];
        res.b += cur.b;
        for (auto& p : ma[x]) {
            if (p == idx) continue;
            dfs2(p, false);
            re -= siz[p];
            ans += 1 + 2 * (siz[p] - 1);
            ans += (2 + 3 * (siz[p] - 1)) * re;
            res.a[1]++, res.a[2] += siz[p] - 1;
        }
        return res;
    };
    rep(i, 0, n - 1) {
        if (r[i] == n) dfs2(i, true);
    }
    cout << ans << endl;
    return;
}

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// NTT求卷积，模数998244353，原根3
// convolution(a, b)返回c，其中c[k]=sum(a[i]*b[j])，i+j=k
constexpr ll MOD = 998244353;
constexpr ll G = 3;

ll qpow(ll x, ll y) {
    ll res = 1;
    while (y) {
        if (y & 1) res = res * x % MOD;
        x = x * x % MOD;
        y >>= 1;
    }
    return res;
}

void ntt(vl& a, bool inv) {
    int n = sz(a);
    for (int i = 1, j = 0; i < n; i++) {
        int bit = n >> 1;
        for (; j & bit; bit >>= 1) j ^= bit;
        j ^= bit;
        if (i < j) swap(a[i], a[j]);
    }
    for (int len = 2; len <= n; len <<= 1) {
        ll wlen = qpow(G, (MOD - 1) / len);
        if (inv) wlen = qpow(wlen, MOD - 2);
        for (int i = 0; i < n; i += len) {
            ll w = 1;
            rep(j, 0, len / 2 - 1) {
                ll u = a[i + j];
                ll v = a[i + j + len / 2] * w % MOD;
                a[i + j] = u + v < MOD ? u + v : u + v - MOD;
                a[i + j + len / 2] = u - v >= 0 ? u - v : u - v + MOD;
                w = w * wlen % MOD;
            }
        }
    }
    if (inv) {
        ll inv_n = qpow(n, MOD - 2);
        for (ll& x : a) x = x * inv_n % MOD;
    }
}

vl convolution(vl a, vl b) {
    if (a.empty() || b.empty()) return {};
    int need = sz(a) + sz(b) - 1;
    int n = 1;
    while (n < need) n <<= 1;
    a.resize(n);
    b.resize(n);
    ntt(a, false);
    ntt(b, false);
    for (int i = 0; i < n; i++) a[i] = a[i] * b[i] % MOD;
    ntt(a, true);
    a.resize(need);
    return a;
}

vl polymul(vl& a, vl& b, int lim) {
    vl c = convolution(a, b);
    if (sz(c) > lim) c.resize(lim);
    return c;
}

vl polypow(vl a, int y, int lim) {
    vl res(1, 1);
    while (y > 0) {
        if (y & 1) res = polymul(res, a, lim);
        y >>= 1;
        if (y) a = polymul(a, a, lim);
    }
    return res;
}

/*
使用示例：

void solve() {
    int n, m;
    cin >> n >> m;
    vl a(n + 1), b(m + 1);
    rep(i, 0, n) cin >> a[i];
    rep(i, 0, m) cin >> b[i];
    vl c = convolution(a, b);
    rep(i, 0, n + m) cout << c[i] << " \n"[i == n + m];
}

输入：
2 1
1 2 3
4 5

输出：
4 13 22 15
*/

constexpr int MX = 4e5 + 5;
ll F[MX];      // 预处理阶乘
ll INV_F[MX];  // 预处理逆元
ll mul(ll x, ll y) { return x * y % MOD; }
ll qpow(ll x, int n) {
    ll res = 1;
    for (; n; n >>= 1) {
        if (n % 2) res = res * x % MOD;
        x = x * x % MOD;
    }
    return res;
}
auto init = [] {
    F[0] = 1;
    for (int i = 1; i < MX; i++) F[i] = F[i - 1] * i % MOD;  // 预处理阶乘
    INV_F[MX - 1] = qpow(F[MX - 1], MOD - 2);
    for (int i = MX - 1; i; i--) {
        INV_F[i - 1] = INV_F[i] * i % MOD;
    }  // 预处理逆元
    return 0;
}();
// 计算C(n,m),即从n个数中取m个数
ll comb(int n, int m) { return m < 0 || m > n ? 0 : F[n] * INV_F[m] % MOD * INV_F[n - m] % MOD; }
void solve() {
    ll n;
    cin >> n;
    vl a(n);
    rep(i, 0, n - 1) cin >> a[i];
    vl pre(n + 1);
    rep(i, 1, n) pre[i] = pre[i - 1] ^ a[i - 1];
    ll tot = pre[n];
    vl c(n + 1);
    rep(i, 0, n) c[i] = mul(F[2 * i], mul(INV_F[i], INV_F[i + 1]));
    vl d(n + 1);
    rep(i, 1, n - 1) d[i] = mul(c[i], c[n - i]);
    ll ans = 0;
    ll tot2 = 0;
    rep(i, 1, n - 1) tot2 = (tot2 + mul(d[i], n + 1 - i)) % MOD;
    rep(i, 0, 17) {
        if ((tot >> i) & 1) {
            ans = (ans + mul(qpow(2, i), tot2)) % MOD;
            continue;
        }
        vl x(n + 1);
        rep(j, 0, n) x[j] = ((pre[j] >> i & 1) ? MOD - 1 : 1);
        auto y = x;
        ranges::reverse(y);
        vl cv = convolution(x, y);
        ll tem = tot2;
        rep(j, 1, n - 1) tem = (tem - mul(d[j], cv[n - j]) + MOD) % MOD;
        ans = (ans + mul(qpow(2, i), tem)) % MOD;
    }
    cout << ans << endl;
    return;
}