Question: What is the runtime of accessing a value in a dictionary by using its key?

  1. O(n), also called linear time.
  2. O(log n), also called logarithmic time.
  3. O(n^2), also called quadratic time.
  4. O(1), also called constant time.

Answer: The correct answer of the above question is Option D:O(1), also called constant time.