Submission #793015

#	Time	Username	Problem	Language	Result	Execution time	Memory
793015		Ahmed_Solyman	XOR (IZhO12_xor)	C++14	100 / 100	155 ms	58400 KiB

xor

#include <bits/stdc++.h>
#include <ext/rope>

using namespace std;
using namespace __gnu_cxx;
#pragma GCC optimize("-Ofast")
#pragma GCC optimize("-O1")
//-------------------------------------------------------------//
typedef long long ll;
typedef unsigned long long ull;
#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define PI acos(-1)
#define lb lower_bound
#define ub upper_bound
#define endl '\n'
#define all(v) v.begin(),v.end()
#define allr(v) v.rbegin(),v.rend()
#define sum_to(n) (n*(n+1))/2
#define pb push_back
#define pf push_front
#define fil(arr,x) memset(arr,x,sizeof(arr))
const ll mod=1e9+7;
int dx[8]={0,1,0,-1,1,1,-1,-1};
int dy[8]={1,0,-1,0,1,-1,-1,1};
//-------------------------------------------------------------//
ll lcm(ll a,ll b)
{
    return (max(a,b)/__gcd(a,b))*min(a,b);
}
void person_bool(bool x)
{
    cout<<(x?"YES":"NO")<<endl;
}
int n,x;
struct node{
    int i;
    node *arr[2];
};
node *New(int i){
    node *ret=new node;
    ret->i=i;
    ret->arr[0]=NULL;
    ret->arr[1]=NULL;
    return ret;
}
void insert(node *root,int xr,int j){
    node *temp=root;
    for(int i=30;i>=0;i--){
        int u=((1<<i)&xr)>0;
        if(temp->arr[u]==NULL){
            temp->arr[u]=New(j);
        }
        temp=temp->arr[u];
    }
}
int query(node *root,int xr){
    int ret=1e9;
    node *temp=root;
    for(int i=30;i>=0;i--){
        int a=((1<<i)&x)>0;
        int b=((1<<i)&xr)>0;
        if(a){
            temp=temp->arr[b^1];
            if(temp==NULL){
                return ret+1;
            }
        }
        else{
            if(temp->arr[b^1]!=NULL){
                ret=min(ret,temp->arr[b^1]->i);
            }
            temp=temp->arr[b];
            if(temp==NULL){
                break;
            }
        }
    }
    if(temp!=NULL){
        ret=min(ret,temp->i);
    }
    return ret+1;
}
signed main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    fast
    cin>>n>>x;
    node *root=New(0);
    insert(root,0,0);
    int xr=0;
    int pos=0,len=-1;
    bool valid=0;
    for(int i=1;i<=n;i++){
        int k;cin>>k;
        xr^=k;
        int j=query(root,xr);
        if(i-j+1>len){
            pos=j;
            len=i-j+1;
        }
        insert(root,xr,i);
    }
    cout<<pos<<" "<<len<<endl;
    return 0;
}

Compilation message (stderr)

xor.cpp: In function 'int main()':
xor.cpp:93:10: warning: unused variable 'valid' [-Wunused-variable]
   93 |     bool valid=0;
      |          ^~~~~

• Subtask 1: 100 / 100