标签:2014百度之星资格赛 字典树
2 3 2 3 4 5 1 5 4 1 4 6 5 6 3
Case #1: 4 3 Case #2: 4
#include<cstdio>
#include<cstdlib>
#include<iostream>
#define LL long long
using namespace std;
LL power[32];
typedef struct TrieNode
{
struct TrieNode *next[2];
}TrieNode;
void Init(TrieNode **root)
{
*root=NULL;
}
TrieNode *CreateNode()
{
TrieNode *p;
p=(TrieNode *)malloc(sizeof(TrieNode));
if(!p)
{
printf("No enough memory!\n");
exit(-1);
}
p->next[0]=NULL;
p->next[1]=NULL;
return p;
}
void InsertNode(TrieNode **root,LL data)
{
int i,k;
TrieNode *p=*root;
if(p==NULL)
{
p=*root=CreateNode();
}
for(i=31;i>=0;i--)
{
if(data&power[i])
k=1;
else
k=0;
if(p->next[k]==NULL)
p->next[k]=CreateNode();
p=p->next[k];
}
}
LL Search(TrieNode *root,LL data)
{
LL ans=0;
TrieNode *p=root;
for(int i=31;i>=0;i--)
{
if(data&power[i])//the No.i bit is 1
{
if(p->next[0])//to get the max xor value the same bit should
p=p->next[0]; // be 0 if it exists
else// if not exist ,then have to choose 1
{
ans|=power[i];
p=p->next[1];
}
}
else//the No.i bit is 0,so we should choose 1 if it exits
{
if(p->next[1])
{
ans|=power[i];
p=p->next[1];
}
else
p=p->next[0];
}
}
return ans;
}
int main(int argc,char *argv[])
{
LL t,n,m;
scanf("%I64d",&t);
for(LL i=1;i<=t;i++)
{
TrieNode *root;
power[0]=1;
for(int j=1;j<=31;j++)
power[j]=power[j-1]<<1;
Init(&root);
printf("Case #%I64d:\n",i);
scanf("%I64d%I64d",&n,&m);
while(n--)
{
LL data;
scanf("%I64d",&data);
InsertNode(&root,data);
}
while(m--)
{
LL s;
scanf("%I64d",&s);
printf("%I64d\n",Search(root,s));
}
}
return 0;
}
2014百度之星资格赛——XOR SUM,布布扣,bubuko.com
标签:2014百度之星资格赛 字典树
原文地址:http://blog.csdn.net/cstopcoder/article/details/26630157