111 lines
2.6 KiB
C
111 lines
2.6 KiB
C
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
|
|
#define HASH_TABLE_SIZE 32
|
|
|
|
// NOTE: the data is some value, which is on a certain 2D point (x,y)
|
|
typedef struct node
|
|
{
|
|
// the data
|
|
int x,y;
|
|
float Value;
|
|
|
|
// next entry in the hash-table, if there were a collision
|
|
struct node *Next;
|
|
}node;
|
|
|
|
#include "linked_list.h"
|
|
|
|
/*
|
|
* Linked-list interface
|
|
*
|
|
* void list_add(node **Head, int Value, int x, int y);
|
|
*
|
|
* node *list_get(node **Head, int x, int y);
|
|
*
|
|
* void list_remove(node **Head, node *Node);
|
|
*
|
|
*/
|
|
|
|
// NOTE: this computes the hash slot of the entry
|
|
int hash(int x, int y)
|
|
{
|
|
int Result = (x + y)%HASH_TABLE_SIZE;
|
|
|
|
if(Result < 0)
|
|
Result *= -1;
|
|
return Result;
|
|
}
|
|
|
|
// NOTE: adds a new entry to the hash table.
|
|
// new entries go at the head of the linked-list
|
|
void hash_add(node **HashTable, float Value, int x, int y)
|
|
{
|
|
// Don't forget to update the hash-tables pointer to the head.
|
|
}
|
|
|
|
// NOTE: gets the note at the position (x,y)
|
|
node *hash_get(node **HashTable, int x, int y)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
// NOTE: removes the node at position (x,y),
|
|
// if there is one
|
|
void hash_remove(node **HashTable, int x, int y)
|
|
{
|
|
|
|
}
|
|
|
|
int main(int argc, char *argv)
|
|
{
|
|
node *HashTable[HASH_TABLE_SIZE] = {};
|
|
|
|
|
|
// NOTE: some test values
|
|
hash_add(HashTable, 1.0, 1, 0);
|
|
hash_add(HashTable, 3.0, 0, 1);
|
|
hash_add(HashTable, 5.0, 3, -2);
|
|
hash_add(HashTable, 7.0, 10, 3);
|
|
|
|
// NOTE: test adding with collisions
|
|
node *Node = hash_get(HashTable, 1, 0);
|
|
if(Node)
|
|
printf("Succesfully added value %f at position (%d,%d) to the HashTable\n", Node->Value, Node->x, Node->y);
|
|
else
|
|
printf("Failed to add or find value 1 at position (1,0)\n");
|
|
|
|
Node = hash_get(HashTable, 0, 1);
|
|
int added01 = 0;
|
|
if(Node)
|
|
{
|
|
printf("Succesfully added value %f at position (%d,%d) to the HashTable\n", Node->Value, Node->x, Node->y);
|
|
added01 = 1;
|
|
}
|
|
else
|
|
printf("Failed to add or find value 3 at position (0,1)\n");
|
|
|
|
Node = hash_get(HashTable, 3, -2);
|
|
if(Node)
|
|
printf("Succesfully added value %f at position (%d,%d) to the HashTable\n", Node->Value, Node->x, Node->y);
|
|
else
|
|
printf("Failed to add or find value 5 at position (-2,-2)\n");
|
|
|
|
Node = hash_get(HashTable, 10, 3);
|
|
if(Node)
|
|
printf("Succesfully added value %f at position (%d,%d) to the HashTable\n", Node->Value, Node->x, Node->y);
|
|
else
|
|
printf("Failed to add or find value 7 at position (10,3)\n");
|
|
|
|
// NOTE: test removing element
|
|
if(added01)
|
|
{
|
|
hash_remove(HashTable, 0, 1);
|
|
Node = hash_get(HashTable, 0, 1);
|
|
if(!Node)
|
|
printf("Succesfully removed entrie at position (0,1) from the HashTable\n");
|
|
else
|
|
printf("Failed to remove entrie at position (0,1)\n");
|
|
}
|
|
}
|