Submission #683849

#	Time	Username	Problem	Language	Result	Execution time	Memory
683849		vovamr	XOR (IZhO12_xor)	C++17	100 / 100	129 ms	46624 KiB

xor

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define fi first
#define se second
#define ll long long
#define ld long double
#define sz(x) ((int)(x).size())
#define all(x) 	(x).begin(), (x).end()
#define pb push_back
#define mpp make_pair
#define ve vector
using namespace std;
using namespace __gnu_pbds;
template<class T> using oset = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
const ll inf = 1e18; const int iinf = 1e9;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T> inline bool chmin(T& a, T b) { return (a > b ? a = b, 1 : 0); }
template <typename T> inline bool chmax(T& a, T b) { return (a < b ? a = b, 1 : 0); }

pii answer = {-1, -1};

const int N = 2.5e5 * 30 + 100;
int w = 0;

int ch[N][2];
int mn[N];

inline void add(const int &x, const int &id) {
	int v = 0;
	for (int i = 29; ~i; --i) {
		int b = x >> i & 1;
		if (!ch[v][b]) ch[v][b] = ++w;
		
		chmin(mn[v], id);
		v = ch[v][b];
	}
	chmin(mn[v], id);
}

inline void relax(const int &x, const int &need, const int &id) {
	int v = 0, ok = 1;
	for (int i = 29; ~i; --i) {
		int b = (x ^ need) >> i & 1;
		int tr = need >> i & 1;

		if (ch[v][b ^ 1] && !tr) {
			int ps = mn[ch[v][b ^ 1]];
			chmax(answer, mpp(id - ps, -(ps + 1)));
		}

		if (!ch[v][b]) {
			ok = 0;
			break;
		}
		v = ch[v][b];
	}
	if (ok) {
		int ps = mn[v];
		chmax(answer, mpp(id - ps, -(ps + 1)));
	}
}

inline void solve() {
	for (int i = 0; i < N; ++i) mn[i] = iinf;

	int n, x;
	cin >> n >> x;

	ve<int> a(n);
	for (auto &i : a) cin >> i;

	int xr = 0;
	for (int i = 0; i < n; ++i) {

		xr ^= a[i];
		if (xr >= x) {
			chmax(answer, mpp(i + 1, -0));
		}

		relax(xr, x, i);
		add(xr, i);
	}

	cout << -answer.se + 1 << " " << answer.fi;
}

signed main() {
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	int q = 1; // cin >> q;
	while (q--) solve();
	cerr << fixed << setprecision(3) << "Time execution: " << (double)clock() / CLOCKS_PER_SEC << endl;
}

• Subtask 1: 100 / 100