Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller.

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Presentation transcript:

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross swap me

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross pointers cross swap with partitioning element

Partitioning in Quicksort n How do we partition the array efficiently? – choose partition element to be rightmost element – scan from right for smaller element – scan from left for larger element – exchange – repeat until pointers cross