Cod sursa(job #1077063)

Utilizator andreiiiiPopa Andrei andreiiii Data 10 ianuarie 2014 20:50:14
Problema Xor Max Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.17 kb
#include <fstream>
#include <cstring>

using namespace std;

const int N=100005;

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

struct Trie
{
    int n;
    Trie *f[2];
    Trie()
    {
        n=0;
        f[0]=f[1]=0;
    }
} *T=new Trie;

int a[N];

void tinsert(Trie *nod, int x, int lvl, int poz)
{
    if(lvl==-1)
    {
        nod->n=poz;
        return;
    }
    int next=((x&(1<<lvl))?1:0);
    if(!nod->f[next]) nod->f[next]=new Trie;
    tinsert(nod->f[next], x, lvl-1, poz);
}

int tquery(Trie *nod, int x, int lvl)
{
    if(lvl==-1) return nod->n;
    int next=((x&(1<<lvl))?1:0);
    if(!nod->f[!next]) return tquery(nod->f[next], x, lvl-1);
    return tquery(nod->f[!next], x, lvl-1);
}

int main()
{
    int n, i, j, sol=-1, solx, soly;
    fin>>n;
    tinsert(T, 0, 20, 0);
    for(i=1;i<=n;i++)
    {
        fin>>a[i];
        a[i]^=a[i-1];
        j=tquery(T, a[i], 20);
        if((a[i]^a[j])>sol)
        {
            sol=(a[i]^a[j]);
            solx=j;
            soly=i;
        }
        tinsert(T, a[i], 20, i);
    }
    fout<<sol<<" "<<solx+1<<" "<<soly;
    fin.close();
    fout.close();
}