Submission #898665

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
898665	2024-01-05T01:37:44 Z	typ_ik	XOR (IZhO12_xor)	C++17	100 / 100	212 ms	87648 KB

xor

#include <bits/stdc++.h>

#define ll long long
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define watch(x) cout << (#x) << " : " << x << '\n'
#define boost ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

using namespace std;

const int N = 3e5 + 128;
const int LOG = 31;
int n, x;
int a[N];

struct node {
    node* nxt[2];
    int min_id;
    node* p;

    node() {
        nxt[0] = nxt[1] = p = nullptr;
        min_id = N;
    }

    void upd() {
        if (nxt[0] != nullptr)
            min_id = min(min_id, nxt[0]->min_id);
        if (nxt[1] != nullptr)
            min_id = min(min_id, nxt[1]->min_id);
    }
};

node* root = new node();

void add(int val, int pos) {
    node* cur = root;

    for (int b = LOG - 1; b >= 0; b--) {
        bool v = ((val >> b) & 1);
        if (cur->nxt[v] == nullptr)
            cur->nxt[v] = new node(), cur->nxt[v]->p = cur;
        cur = cur->nxt[v];
    }

    cur->min_id = min(cur->min_id, pos);

    while (cur != nullptr)
        cur->upd(), cur = cur->p;
}

int get(int val) {
    node* cur = root;

    int ans = N;

    for (int b = LOG - 1; b >= 0 && cur != nullptr; b--) {
        bool v = ((x >> b) & 1);
        bool have = ((val >> b) & 1);
        if (!v && cur->nxt[have ^ 1] != nullptr)
            ans = min(ans, cur->nxt[have ^ 1]->min_id);
        cur = cur->nxt[have ^ v];
    }

    if (cur != nullptr)
        ans = min(ans, cur->min_id);

    return ans;
}

void solve() {
    cin >> n >> x;
    for (int i = 1; i <= n; i++)
        cin >> a[i], a[i] ^= a[i - 1];

    add(0, 0);

    int L = 0, R = -1;
    for (int i = 1; i <= n; i++) {
        add(a[i], i);
        int nl = get(a[i]);
        if (i - nl > R - L)
            L = nl, R = i;
    }

    cout << L + 1 << ' ' << R - L << '\n';
}

main() {
    boost;
    solve();
    return 0;
}

Compilation message

xor.cpp:89:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   89 | main() {
      | ^~~~

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	348 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	1 ms	348 KB	Output is correct
4	Correct	1 ms	600 KB	Output is correct
5	Correct	8 ms	2652 KB	Output is correct
6	Correct	10 ms	2904 KB	Output is correct
7	Correct	10 ms	3060 KB	Output is correct
8	Correct	12 ms	3420 KB	Output is correct
9	Correct	73 ms	41292 KB	Output is correct
10	Correct	75 ms	41296 KB	Output is correct
11	Correct	75 ms	41040 KB	Output is correct
12	Correct	79 ms	41296 KB	Output is correct
13	Correct	79 ms	41296 KB	Output is correct
14	Correct	75 ms	41304 KB	Output is correct
15	Correct	71 ms	41300 KB	Output is correct
16	Correct	71 ms	41344 KB	Output is correct
17	Correct	212 ms	87636 KB	Output is correct
18	Correct	195 ms	87632 KB	Output is correct
19	Correct	210 ms	87648 KB	Output is correct
20	Correct	205 ms	87484 KB	Output is correct