GATE CS 2017 Set 1 — Question 48
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Question
Let be an array of 31 numbers consisting of a sequence of 0's followed by a sequence of 1's. The problem is to find the smallest index such that is 1 by probing the minimum number of locations in . The worst case number of probes performed by an optimal algorithm is ______.
Correct answer
5 to 5
Solution
The array is sorted (all 0s followed by all 1s). Finding the first occurrence of 1 in a sorted array is a search problem where binary search is optimal. For an array of size , the worst-case number of probes (comparisons) in binary search is .
Given :
Worst-case probes = .
Given :
Worst-case probes = .
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