#include <stdio.h>
#include <string.h>
#include <string>
#include <tr1/unordered_map>
#include "trie_tree.h"
using namespace std;
int trie_null(void * v, int f)
{
return 0;
}
class StrHash
{
public:
size_t operator()(const std::string &s) const
{
unsigned int hash = 1315423911;
const char *str = s.c_str();
while (*str)
{
if (*str >= 'A' && *str <= 'Z')
hash ^= ((hash << 5) + (*str++ + ('a' - 'A')) + (hash >> 2));
else
hash ^= ((hash << 5) + (*str++) + (hash >> 2));
}
return (hash & 0x7FFFFFFF);
}
};
class IgnoreCaseComparator
{
public:
bool operator()(const std::string &s1, const std::string &s2) const
{
return (strcasecmp(s1.c_str(), s2.c_str()) == 0);
}
};
typedef std::tr1::unordered_map<const std::string, unsigned long, StrHash, IgnoreCaseComparator> NameTblmetaMap;
int main()
{
trie_tree m_table;
NameTblmetaMap m_tables;
init_trie_tree(&m_table, 100000, trie_null, 0);
for (long i = 11100000; i < 11110000; i++)
{
char buf[20] =
{ 0 };
sprintf(buf, "%ld", i);
m_tables[string(buf)] = i;
insert_trie_tree(&m_table, (unsigned char*) buf, (void*) i);
}
string *slist = new string[1000];
char ** plist = new char*[1000];
for (int i = 0; i < 1000; i++)
{
plist[i] = new char[20];
sprintf(plist[i], "%ld", i + 11100000);
slist[i] = string(plist[i]);
}
struct timespec s, e;
clock_gettime(CLOCK_REALTIME, &s);
for (int i = 0; i < 100000; i++)
{
for (int j = 0; j < 1000; j++)
{
get_trie_tree_value(&m_table, (unsigned char*) plist[j]);
}
}
clock_gettime(CLOCK_REALTIME, &e);
printf("trie %lu\n",
(e.tv_sec - s.tv_sec) * 1000000000 + e.tv_nsec - s.tv_nsec);
clock_gettime(CLOCK_REALTIME, &s);
for (int i = 0; i < 100000; i++)
{
for (int j = 0; j < 1000; j++)
{
m_tables.find(slist[j]);
}
}
clock_gettime(CLOCK_REALTIME, &e);
printf("unordered_map %lu\n",
(e.tv_sec - s.tv_sec) * 1000000000 + e.tv_nsec - s.tv_nsec);
}插入10000条记录，对其中的1000条记录进行查找，做100000轮。
Trie树的耗时为3251830320ns
Stl unordered_map耗时为7080112117ns
多次运行时间波动较小，可见此情况下trie树的速度超过unordered_map两倍
调小插入的记录数至1000时
Trie树的耗时为3195810157
Stl unordered_map耗时为7020927158
变化不大
分别注释掉trie树和unordered_map的插入，不做查找，然后插入11100000-11170000共7万条后，使用pmap查看内存占用
mapped: 19676K writeable/private: 3968K trie
mapped: 22480K writeable/private: 6776K unordered_map
二者实际占用内存只有4-6MB，都比较少，trie树相对更低一些，不过这个场景对trie树的内存占用是有很利的。
