Hash Tables

• Adding an element: simple extension of the algorithm for finding an object
  • Compute the hash code to locate the bucket in which the element should be inserted
  • Try finding the object in that bucket
  • If it is already present, do nothing; otherwise, insert it
• Removing an element is equally simple
  • Compute the hash code to locate the bucket in which the element should be inserted
  • Try finding the object in that bucket
  • If it is present, remove it; otherwise, do nothing
• If there are few collisions, adding or removing takes O(1) time