Definition: A method of open addressing for a hash table in which a collision is resolved by putting the item in the next empty place given by a probe sequence. The space between places in the sequence increases quadratically.
See also double hashing, linear probing.
Note: Deletion may be hard because finding collisions again relies on not creating empty spots. One solution is to mark an entry as deleted so it can be reused for insertion, but the search list is intact.
An explanation of how quadratic equations got their name.
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Entry modified 16 November 2009.
HTML page formatted Tue Dec 6 16:16:32 2011.
Cite this as:
Paul E. Black, "quadratic probing", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 16 November 2009. (accessed TODAY) Available from: http://www.nist.gov/dads/HTML/quadraticprb.html