Cod sursa(job #2634946)

Utilizator OvidRata Ovidiu Ovid Data 12 iulie 2020 19:12:07
Problema Xor Max Scor 90
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.68 kb
#include<bits/stdc++.h>
using namespace std;
#define INIT  ios_base :: sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define mp make_pair
#define pb push_back
#define ft first
#define sc second
#define ll long long
#define pii pair<int, int>
#define count_bits __builtin_popcount
ifstream fin("xormax.in"); ofstream fout("xormax.out");
#define cin fin
#define cout fout

int t, n, m, k, a[100010];
int trie[2100010][2], l=1;
int c[2100000];




void trie_insert(int x){
int crd=1;

for(int i=21; i>=0; i--){
    int ac=( ( (1<<i)&x )>0 )?1:0;
    if(trie[crd][ac]==0 ){
        l++;
        trie[crd][ac]=l;
    }
    crd=trie[crd][ac];
}


}






int trie_find(int x){
int res=0;
int crd=1;




for(int i=21; i>=0; i--){
    int ac=( ( x&(1<<i) )>0 )?1:0;
    if(trie[crd][ac]==0){
        ac=( ac==1  )?0:1;
    }
    res+=ac*(1<<i);
    crd=trie[crd][ac];
}


return res;
}






int32_t main(){
INIT
cin>>n;
a[0]=0;

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



trie_insert(0);
int m=0;
int c1=0, c2=0;
for(int i=1; i<=n; i++){
    trie_insert(a[i]);
    int a2=trie_find(~a[i]);
    c[a[i] ]=i;


    int c3=c[a2 ];
    int c4=i;



    int t=c3; c3=min(c3, c4); c4=max(t, c4);


    if( (a2^a[i])==m ){
        if(c4==c2){
            c1=max(c3, c1);
        }
        if(c4<c2){
            c1=max(c3, c1); c2=c4;
        }
    }


    if( (a2^a[i])>m ){
        m=a2^a[i];
        c2=c4; c1=c3;
    }


    t=c1; c1=min(c1, c2); c2=max(t, c2);


}
cout<<m<<" "<<c1+1<<" "<<c2;




return 0;
}