Let H be a primary min-heap consisting of n elements implemented as an array. What is the worst case time complexity of an optimal algorithm to find the maximum element in H?

Let H be a primary min-heap consisting of n elements implemented as an array. What is the worst case time complexity of an optimal algorithm to find the maximum element in H? Correct Answer θ(n)

Key Points

  • A min-heap is a complete binary tree data structure in which the parent node has a value smaller than its children node.
  • In a min-heap, leaf nodes or the last level contains the maximum values of the array.

Explanation:

If we use the brute force technique, it will take O(n) time to find the largest element in a binary min-heap.

If we use the property of min-heap:

The min-heap property requires that the parent node be lesser than its child node(s). Due to this, we can conclude that a non-leaf node cannot be the maximum element as its child node has a lower value.

So we can narrow down our search space to only leaf nodes. In a min-heap having n elements, there is ceil(n/2) leaf nodes. The time and space complexity remains O(n) as a constant factor of 1/2 does not affect the asymptotic complexity.

Additional Information

 In a min-heap, minimum element takes θ(1).

Related Questions

A teacher asked the class to subtract 5 from 75.70% of the class said: 25. Their work was shown as: \(\begin{array}{*{20}{c}} {\begin{array}{*{20}{c}} 7&5 \end{array}}\\ {\underline {\begin{array}{*{20}{c}}\ { - 5} \ \ \ &{} \end{array}} }\\ {\underline {\begin{array}{*{20}{c}} 2&5 \end{array}} } \end{array}\) Which of the following describes the most appropriate remedial action that the teacher should take to clarify this misconception?