/ build the boolean result array
boolean[] result = new boolean[array.length];
for(int index = 0; index < array.length; index++) {
int num = array[index];
result[num] = true;
}
The result array is the same size as the original array.
But when you do:
int num = array[index];
result[num] = true;
The index being referenced in the result array is dependent on the value of num. So if num is greater than or equal to the length of the array, it throws an ArrayOutOfBoundsException. And what happens when you try sorting an array with elements having the same value?
Eg- try sorting {10,5,9}
Unrelated: HN needs to allow highlighting code inline.
That won't be efficient memorywise since the size of the result array is dependant on the largest value in the array of values.
Consider sorting an array of 2 large integers {65000,30000}. To sort this array, the result array will be initialized with 65000 elements. Very inefficient.
Wouldn't using a sparse bit-array be equivalent to using Bucketsort in space-complexity, but more efficient in time-complexity, or am I missing something here.
I can work up one. Choosing the right bucket will be O(1) as the index is integer. We can store the buckets for lookup in a hash-table or an array-of-arrays, which again will be O(1). Reaching to the actual index should again be O(1) - unless am messing something here.
It could be interpreted as generally applicable. The proposed method uses reverse-indexed flagging, an approach which isn't really feasible if element values are very large.
Generally, the lower bound for any comparison based sorting algorithm is O( n log( n )).
That is true. Just want to add, that the lower bound for sorting is O(n log(n)) for comparison based sorting in infinite universes. The comparison based factor rules out sorting of any element, that can not be reduced to an integer. Infinite universes in sense, that we don't know about the elements/element-range beforehand.
Sorting in ?(n+k) w.c. and a.c. (most of the time this is equal to O(n)) is possible for finite boundaries that allows for countingsort or bucketsort (radixsort uses countingsort internally).
A lot of discussion on bucket/pigeon hole sorting and O(n log n), but nobody mentioning(?):
Integer Sorting in 0(n sqrt (log log n)) Expected Time and Linear Space, Yijie Han and Mikkel Thorup, FOCS '02 Proceedings of the 43rd Symposium on Foundations of Computer Science
Pages 135-144
Is there something like this for designing of databases? software architecture? For example, things like - learning to design a HIPAA compliant user database, designing a micro services architecture for a small but well defined problem etc?
None that I know of and thus the inspiration to start this.
I so intend to write on some pieces of software architecture that I have understanding of. For micro-services piece, if you specific sample well-defined problems, please do let me know and I would like to cover it up.
I think that falls more into the "patterns" space as the problem being solved is not so clear cut. Here is a site with microservices patterns: http://microservices.io/patterns/ .
But when you do:
The index being referenced in the result array is dependent on the value of num. So if num is greater than or equal to the length of the array, it throws an ArrayOutOfBoundsException. And what happens when you try sorting an array with elements having the same value?Eg- try sorting {10,5,9}
Unrelated: HN needs to allow highlighting code inline.
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