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Assume the sequence is increasing, what if we find the largest consecutive difference?
Is the missing element in the middle of the segment with the largest consecutive difference?
For decreasing sequences, just reverse the array and do a similar process.
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Yes, variations of this problem are common in coding interviews because they test understanding of arithmetic progressions, array traversal, and binary search optimization. It is typically categorized as an easy-level problem.
The optimal approach uses binary search to exploit the ordered arithmetic pattern of the array. By comparing the expected value at a midpoint with the actual value, you can determine which half contains the missing number and narrow the search efficiently.
The problem primarily uses an array along with simple mathematical calculations. No additional data structures are required, which keeps the space complexity constant.
You can compute the common difference using the first and last elements of the array. Since one element is missing, the difference can be calculated as (last - first) divided by the total number of elements expected in the progression.