qsort

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qsort is a C standard library function that implements a polymorphic sorting algorithm for arrays of arbitrary objects according to a user-provided comparison function. It is named after the quicksort algorithm, which was originally used to implement it in the Unix C library, although the C standard does not require it to implement quicksort.[1]

Implementations of the qsort function achieve polymorphism by taking a function pointer to a comparison function, as well as a parameter that specifies the size of its individual input objects. The C standard requires the comparison function to implement a total order on the items in the input array.[2]

References[edit]

  1. ^ Bentley, Jon L.; McIlroy, M. Douglas (1993). "Engineering a sort function". Software—Practice and Experience 23 (11): 1249–1265. doi:10.1002/spe.4380231105. 
  2. ^ ISO/IEC 9899:201x, Programming Languages—C (draft). §7.22.5. November 16, 2010.