Stdsort

Stdsort is not a function defined by the C++ Standard Library. In standard C++, there is no stdsort; the sorting facilities are provided by std::sort and related functions. If you encounter the name stdsort, it is usually a typo for std::sort or a non-standard extension in a particular library.

Std::sort is declared in the <algorithm> header and operates on a range defined by two iterators: sort(first, last) sorts the elements in the half-open range [first, last) into nondecreasing order. By default it uses operator< for comparisons, but a custom comparison function or functor can be supplied as a third argument to define the ordering. Sorting is not guaranteed to be stable; equal elements may change order relative to one another.

In practice, std::sort is typically implemented as an introsort hybrid algorithm, combining quicksort with heapsort and insertion sort for small partitions. This approach generally provides strong practical performance across a wide variety of inputs. The time complexity is commonly described as O(n log n) on average, with good worst-case behavior achieved by the hybrid approach, although the standard does not prescribe a specific worst-case bound.

If stability is required, the standard provides std::stable_sort, which preserves the relative order of equivalent elements and will generally run in O(n log n) time as well, though with different performance characteristics and memory usage.

Summary: stdsort is not a standard function in C++. Use std::sort (or std::stable_sort when stability is needed) from <algorithm>. If you see stdsort in code, it is likely a typo or a non-standard extension.

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