A New Look at Worst Case Complexity: A Statistical Approach

Algorithm 2

The “C” code implementation of the naive (first element pivot) quick sort.

// System Specification: as given in main text

int main (int argc, char *argv)

{

⋯⋯⋯⋯⋯⋯⋯

 quicksort( A, low, high);

⋯⋯⋯⋯⋯⋯⋯

}

quicksort(int A, int low, int high)

{

 int p;

 if(low>=high)

 return;

 p=partition(A,low,high);

 quicksort(A,low,p-1);

 quicksort(A,p+1,high);

}

int partition(int A, int low, int high)

{

 int temp,key,i,j;

 key = Alow;

 i=low+1;

 j=high;

 while(i <= j)

 {

    while(Ai <= key && i<=j)

    {

    i++;

    }

    while(Aj > key && i <= j)

    {

    j- -;

    }

    if(i <= j)

    {

     temp=Ai;

     Ai=Aj;

     Aj=temp;

    }

   }

   Alow=Aj;

   Aj=key;

   return(j);

}