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| #include <iostream>
#include <cstdio>
#include <queue>
#include <algorithm>
#define maxn 1000010
#define INF 1000000000
#define ll long long
#define lowbit(i) ((i) & (-i))
using namespace std;
int n, m;
ll a[maxn];
ll mx[maxn], mn[maxn], v[maxn], ans, w[maxn], W[maxn], M;
void solve(int l, int r) {
if (l == r) return (void) (ans ^= a[l]); int m = l + r >> 1, cx = m, cn = m;
mn[m + 1] = mx[m + 1] = a[m + 1]; mn[m] = mx[m] = a[m];
w[m] = W[m] = v[m] = 0; W[m + 1] = w[m + 1] = v[m + 1] = a[m + 1];
for (int i = m + 2; i <= r; ++i) {
mn[i] = min(a[i], mn[i - 1]);
mx[i] = max(a[i], mx[i - 1]);
v[i] = v[i - 1] ^ (mx[i] | mn[i]);
w[i] = w[i - 1] ^ mx[i];
W[i] = W[i - 1] ^ mn[i];
}
for (int i = m; i >= l; --i) {
while (cx < r && mx[cx + 1] <= mx[i]) ++cx;
while (cn < r && mn[cn + 1] >= mn[i]) ++cn;
ans ^= (min(cx, cn) - m & 1) * (mn[i] | mx[i]);
if (cx < cn) {
ll v = w[cn] ^ w[cx];
if (cn - cx & 1) v |= mn[i];
else v &= M ^ mn[i];
ans ^= v;
}
else if (cx > cn) {
ll v = W[cx] ^ W[cn];
if (cx - cn & 1) v |= mx[i];
else v &= M ^ mx[i];
ans ^= v;
}
ans ^= v[r] ^ v[max(cn, cx)];
mx[i - 1] = max(mx[i], a[i - 1]);
mn[i - 1] = min(mn[i], a[i - 1]);
}
solve(l, m); solve(m + 1, r);
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
cin >> n; M = (1ll << 60) - 1;
for (int i = 1; i <= n; ++i) cin >> a[i];
solve(1, n); cout << ans << "\n";
return 0;
}
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