Testing if an Array Is Sorted
نویسنده
چکیده
Suppose we would like to check whether a given array of real numbers is sorted (say, in nondecreasing order). Performing this task exactly requires reading the entire array. Here we consider the approximate version of the problem: testing whether an array is sorted or “far” from sorted. We consider two natural definitions of the distance of a given array from a sorted array. Intuitively, we would like to measure how much the input array must change to become sorted. We could measure the change by
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