Submission #883487

#	Time	Username	Problem	Language	Result	Execution time	Memory
883487		NintsiChkhaidze	XOR (IZhO12_xor)	C++17	100 / 100	144 ms	39452 KiB

xor

#include <bits/stdc++.h>
#define pb push_back
#define s second
#define f first
#define left (h<<1),l,(l + r)/2
#define right ((h<<1)|1),(l + r)/2 + 1,r
#define pii pair<int,int>
#define ll long long
// #define int ll
using namespace std;

const int N = 250000 + 5;

int a[N],p[N],tot = 1,child[N * 33][4],val[N * 33];

void upd(int k,int i){
	int cur = 1;
	for (int j = 30; j >= 0; j--){
		int b = (k & (1<<j)) > 0;
		if (!child[cur][b]){
			child[cur][b] = ++tot;
		}
		cur = child[cur][b];
		val[cur] = max(val[cur],i);
	}	
}

int find(int i,int mask,int lim){
	// ... == mask ^ p[i - 1]
	
	mask ^= p[i - 1];
	int cur = 1;

	for (int j = 30; j >= lim; j--){
		int b = (mask & (1<<j)) > 0;
		if (!child[cur][b]) return -1;
		cur = child[cur][b];
	}

	return val[cur] - i + 1;
}

signed main (){
    ios_base::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL);
	
	// freopen("game.in", "r", stdin);
	// freopen("game.out", "w", stdout);

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

	for (int i = 1; i <= n; i++){
		cin >> a[i];
		p[i] = p[i - 1] ^ a[i];
	}

	int ans1 = 0,ans2 = 0;
	for (int i = n; i >= 1; i--){
		upd(p[i],i);
		int res = find(i,x,0);
		if (res >= ans2) ans1 = i,ans2 = res;  

		int mask = 0;
		for (int j = 30; j >= 0; j--){
			if (!(x & (1<<j))){
				int res = find(i,(mask ^ (1<<j)),j);
				if (res >= ans2) ans1=i,ans2=res;  
			}
			mask ^= (x & (1<<j));
		}
	}

	cout<<ans1<<" "<<ans2;
}

• Subtask 1: 100 / 100