Hashing algorithm using index value ranges.

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I'm trying to make a hash that stores data based on a index value range instead of a single index value.

This should help explain what I mean:

________________________________________________<br />
<br />
=== PSEUDO CODE ===<br />
/* function: hash_insert(int lower_bound, int upper_bound, string data); */<br />
<br />
hash_insert(4, 11, "found me!");<br />
hash_insert(16, 19, "where am I?");<br />
<br />
print( hash_find(18) );<br />
print( hash_find(5) );<br />
<br />
=== PROGRAM OUTPUT ===<br />
where am I?<br />
found me!<br />
________________________________________________<br />

There isn't a particular pattern to the value ranges.

I'm stumped. Does anyone have a clue? :((

Posted 30-Nov-10 15:46pm

Gravis Zero

Updated 30-Nov-10 16:19pm

v3

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Andreas Gieriet · Answer 1 · 2010-12-16T11:06:00

Depending on the amount of potential entries and the size of the ranges, you might consider to go a brute-force approach:

--> Add for each number in the hash_insert(...) range a dedicated entry in the hash table.

I.e. the hash_insert(...) function is a convenience function for multiple consecutive single_hash_insert(...) calls.

May sound silly, but maybe it solves your problem.

Cheers

Andi

R. Erasmus · Answer 2 · 2010-12-16T22:39:00

Is this what you're looking for?
It basically checks whether data written to the function falls in range of the saved data.

hash_insert(int lower_bound, int upper_bound, string data)
{
  static int saved_range_lower;
  static int saved_range_upper;
  if (data.Contains("?") == true)
  {
    saved_range_lower = lower_bound;
    saved_range_upper = upper_bound;
  }
  else
  {
    if((lower_bound >= saved_range_lower) &&
       (lower_bound <= saved_range_upper) &&
       (upper_bound >= saved_range_lower) &&
       (upper_bound <= saved_range_upper))
    {
      data = "found me!";
    }
    else
    {
      data = "where am I?"
    }
  }
}

Hashing algorithm using index value ranges.

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