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Why does putting names in alphabetical order make searching a list faster?

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Ordering a list alphabetically makes searching significantly faster because it enables the use of a binary search technique.

In an unsorted list, you must examine each item sequentially to find a match, which is inefficient. However, when a list is sorted lexicographically (alphabetical order), you can repeatedly cut the remaining search area in half. By comparing the target name to the middle element of the current range, you can immediately determine whether the target resides in the first or second half of the list, allowing you to discard the other half entirely. This process continues until the item is located, drastically reducing the number of comparisons required compared to a linear search.1

This efficiency is a core concept in computational complexity, which measures the time and resources an algorithm requires to function. By organizing data into a structured format, you transform a potentially time-consuming task into one that can be solved much more rapidly.21