Cod sursa(job #3189909)

Utilizator PetraPetra Hedesiu Petra Data 6 ianuarie 2024 17:36:15
Problema Xor Max Scor 10
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.39 kb
#include <iostream>
#include <fstream>

#define x first
#define poz second
#define NMAX 100002

using namespace std;

ifstream fin ("xormax.in");
ofstream fout ("xormax.out");


struct trie {
    int val, poz;
    trie *bit[2];
    trie() {
        val = poz = 0;
        bit[0] = bit[1] = NULL;
    }
};

trie *T = new trie;

void ins(trie *nod, int x, int poz)
{
    for (int i = 25; i >= 0; i--)
    {
        int bit = (x >> i) & 1;

        if (nod->bit[bit] == 0)
            nod->bit[bit] = new trie;

        nod = nod->bit[bit];
    }
    nod->val = x;
    nod->poz = poz;
}

pair<int, int> trie_query(trie *nod, int x)
{
    for (int i = 25; i >= 0; i--)
    {
        int bit = (x >> i) & 1;

        if(nod->bit[!bit] != 0)
            nod = nod->bit[!bit];
        else
            nod = nod->bit[bit];
    }
    return make_pair(nod->val, nod->poz);
}

int n, mx = -1, st, dr, v[NMAX];
int main()
{
    fin >> n;

    ins(T, 0, 0);

    int prefix = 0;
    for (int i = 1; i <= n; i++)
    {
        fin >> v[i];
        v[i] = v[i] ^ v[i-1];

        pair<int, int> aux = trie_query(T, v[i]);
        if (v[i] ^ v[aux.poz] > mx)
        {
            mx = v[i] ^ v[aux.poz];
            st = aux.poz + 1;
            dr = i;
        }

        ins(T, v[i], i);
    }
    fout << mx << " " << st << " " << dr;
    return 0;
}