Why sorting gets slow so fast: bubble sort versus merge sort and n log n
30seconds
Two sorting methods can both be perfectly correct and still differ by a factor of 25,000 on a big list.
Race bubble sort against merge sort on the same shuffled bars, watch the comparison counters, then slide the list size up to a billion and see why doubling the input can quadruple the work for one method and barely more than double it for the other.
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