Problem 56040. A Binary Search
 Calculate the index of the midpoint of the array X by taking the average of the largest and smallest indices and rounding to the nearest integer.
 If the value located at the midpoint matches your target, set found to true.
 If the target is less than the value located at the midpoint of X, narrow your search to the lower half of X by setting the largest index in the array to the midpoint  1.
 If the target is greater than the value located at the midpoint of X, narrow your search to the upper half of X by setting the smallest index in the array to the midpoint + 1.
 Repeat the steps above until found is true.
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This is a good exercise, but you can't enforce people to do a binary search in a programming competition unless you can find a way to identify a search done with a binary search uniquely.
Maybe requiring that the sequence of midpoints until a key is retrieved is returned as part of the solution. It would make it harder to "cheat".
You can add the incrementation of the number of iterations in your algorithm's description and test its exact value in the test suite.
Very interesting problem, thanks!
I would like to know if anyone else is getting a discrepancy in tests 5 and 6. My number of iterations is one less than the expected in those two test sets. I had to start my iteration counter with 2 to get the expected results.
@Jose, it's not a discrepancy, that is how one is suppose to calculate the number of iterations for this problem, as you can see from the example in the problem description.
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