Cod sursa(job #581298)

Utilizator drywaterLazar Vlad drywater Data 13 aprilie 2011 23:24:05
Problema Xor Max Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.07 kb
#include <stdio.h>
int n,a,b,i,x[100001],A,max;
struct Trie
{
    int poz;
    Trie *fiu[2];
    Trie()
    {
        poz=0;
        fiu[0]=fiu[1]=0;
    }
};
Trie *t=new Trie;
int caut(Trie *nod,int val,int bit)
{
    Trie *R=nod;
    while (bit!=-1)
    {
        int x=((val&(1<<bit))>>bit);
        if (R->fiu[x^1]) R=R->fiu[x^1];
        else R=R->fiu[x];
        bit--;
    }
    if (max<x[R->poz]^val)
    {
        max=x[R->poz]^val;
        a=(R->poz)+1;
        b=i;
    }
    return 0;

}
int ins(Trie *nod,int val,int bit)
{
    if (bit==-1)
    {
        nod->poz=i;
        return 0;
    }
    int x=(((1<<bit)&val)>>bit);
    if (nod->fiu[x]==0) nod->fiu[x]=new Trie;
    bit--;
    ins(nod->fiu[x],val,bit);
}
int main(void)
{
    freopen("xormax.in","r",stdin);
    freopen("xormax.out","w",stdout);
    scanf("%d",&n);
    ins(t,0,24);
    for (i=1;i<=n;i++)
    {
        scanf("%d",&A);
        x[i]=x[i-1]^A;
        caut(t,x[i],24);
        ins(t,x[i],24);

    }
    printf("%d %d %d\n",max,a,b);
    return 0;
}