As assignment for Data Structures and Algorithms course, we had to work with a modified version of the quicksort algorithm. It came obvious that for modifying a qsort you need to implement it

It is difficult to find a clear quicksort algorithm implemented, so I wrote it.

Here is the generic C implementation of the Quicksort Algorithm, which sorts an array in place, following the Divide And Conquer design.

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int partition( int A[], int left, int right) { int pivot; pivot = A[right]; while(1){ while( A[right] > pivot){ right--; } while( A[left] < pivot){ left++; } if( left < right ){ swap(A,left,right); }else{ return left; } } } void quicksort( int A[], int left, int right){ int m; if( left < right ) { m = partition( A, left, right); quicksort( A, left, m-1); quicksort( A, m+1, right); } } |

As you see, there is nothing optimized in this implementation. It just looks elegant and easy to be understood.

If you would like to have a more optimized version of this algorithm, take a look at this one.