example.c

google hash table算法

#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <time.h>

#include "libchash.h"

static void TestInsert() {
  struct HashTable* ht;
  HTItem* bck;

  ht = AllocateHashTable(10, 0);    /* value is 1 byte, 0: don't copy keys */

  HashInsert(ht, PTR_KEY(ht, "January"), 31);  /* 0: don't overwrite old val */
  bck = HashInsert(ht, PTR_KEY(ht, "February"), 28);
  bck = HashInsert(ht, PTR_KEY(ht, "March"), 32);
  bck = HashInsert(ht, PTR_KEY(ht, "Februaryw"), 11);


  bck = HashFind(ht, PTR_KEY(ht, "Februaryw"));
  printf("%d\t%d\n", bck->data, bck->key);		  	
  bck = HashFind(ht, PTR_KEY(ht, "March"));
  printf("%d\t%d\n", bck->data, bck->key);		  	

  bck = HashFind(ht, PTR_KEY(ht, "February"));
  printf("%d\t%d\n", bck->data, bck->key);		  	
//  assert(bck);
//  assert(bck->data == 28);

  FreeHashTable(ht);
}

static void TestFindOrInsert() {
  struct HashTable* ht;
  int i;
  int iterations = 1000000;
  int range = 30;         /* random number between 1 and 30 */
	
  ht = AllocateHashTable(4, 0);    /* value is 4 bytes, 0: don't copy keys */

	HashInsert(ht, 1, 8888);
	HashInsert(ht, 1, 666);
	
  /* We'll test how good rand() is as a random number generator */

//  for (i = 0; i < iterations; ++i) {
//    int key = rand() % 100; //range;
//    HTItem* bck = HashFindOrInsert(ht, key, 0);     /* initialize to 0 */
//    bck->data++;                   /* found one more of them */
//  }

  for (i = 0; i < 10; ++i) {
    HTItem* bck = HashFind(ht, i);
    if (bck) {
      printf("%3d: %d\n", bck->key, bck->data);  
			
    } else {
 //     printf("%3d: 0\n", i);
    }
  }

// PrintHashTable(ht, 0, 2);

  FreeHashTable(ht);
}

int main(int argc, char** argv) {
  TestInsert();
  TestFindOrInsert();
  return 0;
}