Submission #901297

#	Time	Username	Problem	Language	Result	Execution time	Memory
901297		borademirtas	XOR (IZhO12_xor)	C++17	100 / 100	172 ms	60496 KiB

xor

#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#pragma GCC optimize("O3,unroll-loops")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
#define ll long long
#define  vll vector<ll>
#define pb push_back
#define vp vector<pll>
#define tc ll t; cin >> t; for(ll i = 0; i < t; i++){solve(i, t);}
#define tc1 solve(1, 1);
#define mpvll map<ll, vll>
#define vfast vll a(n); for (ll i = 0; i < n; i++) { cin >> a[i]; }
#define mpll map<ll,ll>
#define pll pair<ll,ll>
#define vll2 vector<vector<ll>> dp(n, vector<ll>(m));
#define FIXED(A) cout << fixed; cout.precision(20); cout << A << "\n";
#define mp(A, B) make_pair(A, B)
#define all(x) (x).begin(), (x).end()
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define sz(x) (int)(x).size()
#define big __int128
#define F first
#define S second
#define ckmin(a,b) a = min(a,b)
#define ckmax(a,b) a = max(a,b)
template <typename num_t>
using indexed_set = tree<num_t, null_type, less<num_t>, rb_tree_tag, tree_order_statistics_node_update>;
void setIO(string name) {freopen((name+".in").c_str(),"r",stdin);freopen((name+".out").c_str(),"w",stdout);}
ll rd(ll a, ll b){return (a+b-1) / b;}
ll isqrt(ll x){ll ans = 0; for(ll k = 1LL << 30; k != 0; k /= 2){if ((ans + k) * (ans + k) <= x) {ans += k;} } return ans;   }
vll prime(ll x){ll n = x; vll ans; while (n % 2 == 0) {ans.pb(2);n = n/2;} for (int i = 3; i <= sqrt(n); i = i + 2) {while (n % i == 0){ans.pb(i);n = n/i;}}if (n > 2){ans.pb(n);} return ans;}
ll binpow(ll a, ll b, ll m) { a %= m; ll res = 1; while (b > 0) { if (b & 1){res = res * a % m;}a = a * a % m; b >>= 1;} return res;}
ll lg2(ll n){ll cnt=0;while(n){cnt++;n/=2;}return cnt;}

struct Node{
    Node *c[2]; ll cnt = 2e9;

};
Node *root = new Node();

void update(ll x, ll pos){
    Node *cur = root;
    for(ll i = 33; i >= 0; i--){
        ckmin(cur->cnt, pos);
        if(x&(1LL<<i)){
            if(!cur->c[1]){cur->c[1] = new Node(); cur = cur->c[1]; cur->cnt=pos; }
            else{cur=cur->c[1]; }
        }
        else{
            if(!cur->c[0]){cur->c[0] = new Node(); cur = cur->c[0]; cur->cnt=pos;   }
            else{cur=cur->c[0]; }
        }
    }
}


ll query(ll x, ll k){

    Node *cur = root; ll best = 2e9;ll val = 0;

    for(ll i = 33; i >= 0 ; i--){

        if(cur->c[1]){
            if(!(x&(1LL<<i))){
                if((1LL<<i)+val >= k){ckmin(best, cur->c[1]->cnt);}
            }
        }
        if(cur->c[0]){
            if(x&(1LL<<i)){
                if((1LL<<i)+val >= k){ckmin(best, cur->c[0]->cnt);}
            }
        }

        if(((x>>i)&1LL) == ((k>>i)&1LL)){
            if(cur->c[0]){
                if(k&(1LL<<i)){val += (1LL<<i);}
                cur = cur->c[0];
                if(val>=k){ckmin(best, cur->cnt);}
            }
            else{
                if(val>=k){ckmin(best, cur->cnt);}
                return best;
            }

        }
        else{
            if(cur->c[1]){
                if(k&(1LL<<i)){val += (1LL<<i);}
                cur = cur->c[1];
                if(val>=k){ckmin(best, cur->cnt);}
            }
            else{
                if(val>=k){ckmin(best, cur->cnt);}
                return best;
            }

        }

    }
    return best;
}


void solve(ll TC, ll TC2) {

    ll n, k; cin >> n >> k;
    vll a(n); for(ll i = 0; i < n; i++){cin >> a[i];}

    ll pre = 0;
    ll idx = -1, sz = -1;
    update(0,-1);
    for(ll i = 0; i < n; i++){
        pre^=a[i];
        ll val = query(pre,k);
        if(i-val>sz){sz=i-val; idx = val+1;}
        if(pre>=k){sz=i+1; idx=0;}
        update(pre,i);
    }

    cout << idx+1 << " " << sz << '\n';


}




int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);
    tc1
}

Compilation message (stderr)

xor.cpp: In function 'void setIO(std::string)':
xor.cpp:31:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 | void setIO(string name) {freopen((name+".in").c_str(),"r",stdin);freopen((name+".out").c_str(),"w",stdout);}
      |                          ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
xor.cpp:31:73: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 | void setIO(string name) {freopen((name+".in").c_str(),"r",stdin);freopen((name+".out").c_str(),"w",stdout);}
      |                                                                  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100