Pagini recente » Cod sursa (job #2025806) | Cod sursa (job #2531487) | Cod sursa (job #1498482) | Cod sursa (job #1421687) | Cod sursa (job #605300)
Cod sursa(job #605300)
#include <fstream>
#include <iostream>
#include <string.h>
#define MAXN 100001
#define MAX_BITS 31
using namespace std;
typedef unsigned int uint32;
uint32 sums[MAXN];
struct TrieData
{
int index;
TrieData *child[2];
};
class CTrie
{
public:
CTrie()
{
Trie.index = -1;
memset(Trie.child, 0, 2*sizeof(TrieData*));
}
inline void addElement(const uint32 num, const int index)
{
uint32 i;
int childIndex;
TrieData *ptr = &Trie;
for (i = 1<<MAX_BITS; i; i>>=1)
{
childIndex = !(!(num & i));
if (!ptr->child[childIndex])
{
ptr->child[childIndex] = allocElement();
}
ptr = ptr->child[childIndex];
}
ptr->index = index;
}
inline int findMaximizingElement(const uint32 num) const
{
uint32 i;
int childIndex;
const TrieData *ptr = &Trie;
for (i = 1<<MAX_BITS; i; i>>=1)
{
childIndex = !(num & i);
if (ptr->child[childIndex])
ptr = ptr->child[childIndex];
else
ptr = ptr->child[!childIndex];
}
return ptr->index;
}
private:
TrieData Trie;
inline TrieData* allocElement(const int index = -1) const
{
TrieData *elem = new TrieData;
elem->index = index;
memset(elem->child, 0, 2*sizeof(TrieData*));
return elem;
}
};
int main()
{
unsigned long N, x, sum=0;
long maxsum, indMin, indMax;
fstream fin("xormax.in", fstream::in);
fstream fout("xormax.out", fstream::out);
CTrie Trie;
fin>>N;
//cout<<N<<endl;
maxsum=-1;
for(int i=0; i<N; ++i)
{
fin >> x;
sum^=x;
sums[i] = sum;
//cout << sums[i] << " ";
Trie.addElement(sums[i], i);
}
//cout<<endl;
for (int i=0; i<N; ++i)
{
const int index = Trie.findMaximizingElement(sums[i]);
if (sums[i]^sums[index] >= maxsum)
{
maxsum = sums[i]^sums[index];
i>index ? (indMin = index+1, indMax = i) : (indMin = i+1, indMax = index);
}
}
fout << maxsum << " " << indMin+1 << " " << indMax+1 << endl;
fin.close();
fout.close();
return 0;
}