16. Mergesort 8 12 11 2 7 5 4 10 Split the list in half. 8 12 4 10 Mergesort the left half. Split the list in half. Mergesort the left half. 4 10 Split the list in half. Mergesort the left half. 10 Mergesort the right. 4 http://ecomputernotes.com
17. Mergesort 8 12 11 2 7 5 4 10 8 12 4 10 4 10 Mergesort the right half. Merge the two halves. 10 4 8 12 12 8 Merge the two halves . 8 8 12 http://ecomputernotes.com
18. Mergesort 8 12 11 2 7 5 4 10 8 12 4 10 Merge the two halves. 4 10 Mergesort the right half. Merge the two halves. 10 4 8 12 10 12 8 4 10 4 8 12 http://ecomputernotes.com
39. Merge Sort and Linked Lists Sort Sort Merge http://ecomputernotes.com
40.
41.
42.
43. Quicksort First the list is partitioned around a pivot value. Pivot can be chosen from the beginning, end or middle of list): 8 3 2 11 7 5 4 10 12 4 5 5 pivot value http://ecomputernotes.com
44. Quicksort The pivot is swapped to the last position and the remaining elements are compared starting at the ends. 8 3 2 11 7 5 4 10 12 4 5 low high 5 pivot value http://ecomputernotes.com
45. Quicksort Then the low index moves right until it is at an element that is larger than the pivot value (i.e., it is on the wrong side) 8 6 2 11 7 5 10 12 4 6 low high 5 pivot value 3 12 http://ecomputernotes.com
46. Quicksort Then the high index moves left until it is at an element that is smaller than the pivot value (i.e., it is on the wrong side) 8 6 2 11 7 5 4 10 12 4 6 low high 5 pivot value 3 2 http://ecomputernotes.com
47. Quicksort Then the two values are swapped and the index values are updated: 8 6 2 11 7 5 4 10 12 4 6 low high 5 pivot value 3 2 12 http://ecomputernotes.com
48. Quicksort This continues until the two index values pass each other: 8 6 12 11 7 5 4 2 4 6 low high 5 pivot value 3 10 3 10 http://ecomputernotes.com
49. Quicksort This continues until the two index values pass each other: 8 6 12 11 7 5 4 2 4 6 low high 5 pivot value 10 3 http://ecomputernotes.com
50. Quicksort Then the pivot value is swapped into position: 8 6 12 11 7 5 4 2 4 6 low high 10 3 8 5 http://ecomputernotes.com
51. Quicksort Recursively quicksort the two parts: 5 6 12 11 7 8 4 2 4 6 10 3 Quicksort the left part Quicksort the right part 5 http://ecomputernotes.com
52. Quicksort void quickSort(int array[], int size) { int index; if (size > 1) { index = partition(array, size); quickSort(array, index); quickSort(array+index+1, size - index-1); } } http://ecomputernotes.com
53. int partition(int array[], int size) { int k; int mid = size/2; int index = 0; swap(array, array+mid); for (k = 1; k < size; k++){ if (array[k] < array[0]){ index++; swap(array+k, array+index); } } swap(array, array+index); return index; } Quicksort
