1. Array Based Collections
Stack and ArrayList
Array Based Collections

2. Collections Arrays Collections Primitive structured storage
Higher level storage structures
Lists
Stacks/Queues
Sets
Trees
Graphs…

3. Stack Collection where we can only work with "top"
Peek() : get value on top
Pop() : remove value on top
Push(value) : put new value on top

4. Stack
LIFO : Last in First Out

5. Internal Structure Stack after pushing 5, 10, 20 capacity = 10
size = 3 elements = □ 1 2 3 4 5 6 7 8 9 10 20 ??

6. Constructor Default capacity = 10 Array of uninitialized values
size = 0 elements = □ 1 2 3 4 5 6 7 8 9 ??

7. Push Pushing 15 Size indicates next available slot capacity = 10
size = 3 elements = □ 1 2 3 4 5 6 7 8 9 10 20 ??

8. Push Pushing 15 Size indicates next available slot capacity = 10
size = 3 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

9. Push Pushing 15 Size indicates next available slot capacity = 10
size = 4 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

10. Growing When run out of room allocate new array, copy delete old
capacity = 5
size = 5 elements = □ 1 2 3 4 5

11. Growing When run out of room allocate new array, copy delete old
capacity = 5
size = 5 elements = □
old = □ 1 2 3 4 5

12. Growing When run out of room allocate new array, copy delete old
capacity = 10
size = 5 elements = □
old = □ 1 2 3 4 5 1 2 3 4 5 6 7 8 9 ??

13. Growing When run out of room allocate new array, copy delete old
capacity = 10
size = 5 elements = □
old = □ 1 2 3 4 5 1 2 3 4 5 6 7 8 9 ??

14. Growing When run out of room allocate new array, copy delete old
capacity = 10
size = 5 elements = □
old = □ 1 2 3 4 5 6 7 8 9 ??

15. Growing When run out of room allocate new array, copy delete old
capacity = 10
size = 5 elements = □ 1 2 3 4 5 6 7 8 9 ??

16. Peek Peek Size – 1 indicates "top" element capacity = 10
size = 4 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

17. Pop Pop Predecrement happens before access
Old item not part of logical stack
capacity = 10
size = 4 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

18. Pop Pop Predecrement happens before access
Old item not part of logical stack
capacity = 10
size = 3 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

19. Usual Suspects
Manage memory so…
Copy Constructor
Destructor

20. Split Split Return new Stack with top half capacity = 10
size = 4 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

21. Split Split Return new Stack with top half top this capacity = 10
size = 0 elements = □
capacity = 10
size = 4 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ?? 1 2 3 4 5 6 7 8 9 ??

22. Split Split Return new Stack with top half top this capacity = 10
size = 0 elements = □
capacity = 10
size = 4 elements = □
myNewSize = 2 1 2 3 4 5 6 7 8 9 10 20 15 ?? 1 2 3 4 5 6 7 8 9 ??

23. Split Split Return new Stack with top half top this capacity = 10
size = 1 elements = □
capacity = 10
size = 4 elements = □
myNewSize = 2 1 2 3 4 5 6 7 8 9 10 20 15 ?? 1 2 3 4 5 6 7 8 9 20 ??

24. Split Split Return new Stack with top half top this capacity = 10
size = 2 elements = □
capacity = 10
size = 4 elements = □
myNewSize = 2 1 2 3 4 5 6 7 8 9 10 20 15 ?? 1 2 3 4 5 6 7 8 9 20 15 ??

25. Split Split Return new Stack with top half top this capacity = 10
size = 2 elements = □
capacity = 10
size = 2 elements = □
myNewSize = 2 1 2 3 4 5 6 7 8 9 10 20 15 ?? 1 2 3 4 5 6 7 8 9 20 15 ??

26. Split Split Return new Stack with top half topPart this capacity = 10
size = 0 elements = □
capacity = 10
size = 2 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ?? 1 2 3 4 5 6 7 8 9 20 15 ??

27. Clear Clear Change logical size to 0 capacity = 10
size = 4 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

28. Clear Clear Change logical size to 0 capacity = 10
size = 0 elements = □ 1 2 3 4 5 6 7 8 9 10 20 15 ??

29. ArrayList
ArrayList
Acts like a list
Implemented with array

30. Code Tour Same structure as Stack Pointer to dynamic array
Maintain logical/maximum size

31. Code Tour Constructor capacity = 10 currentSize = 0 list = □ 1 2 3 4 51 2 3 4 5 6 7 8 9 ??

32. Code Tour Append 'U' capacity = 10 currentSize = 1 list = □ 1 2 3 4 51 2 3 4 5 6 7 8 9 U ??

33. Code Tour Insert 'Q' at 2 capacity = 10 currentSize = 4 list = □ 1 2 31 2 3 4 5 6 7 8 9 U C L A ??

34. Code Tour Insert 'Q' at 2 capacity = 10 currentSize = 4 list = □ i = 41 2 3 4 5 6 7 8 9 U C L A ??

35. Code Tour Insert 'Q' at 2 capacity = 10 currentSize = 4 list = □ i = 41 2 3 4 5 6 7 8 9 U C L A ??

36. Code Tour Insert 'Q' at 2 capacity = 10 currentSize = 4 list = □ i = 31 2 3 4 5 6 7 8 9 U C L A ??

37. Code Tour Insert 'Q' at 2 capacity = 10 currentSize = 4 list = □ 1 2 31 2 3 4 5 6 7 8 9 U C Q L A ??

38. Code Tour Insert 'Q' at 2 capacity = 10 currentSize = 5 list = □ 1 2 31 2 3 4 5 6 7 8 9 U C Q L A ??

39. Code Tour Remove at 2 capacity = 10 currentSize = 5 list = □ 1 2 3 4 51 2 3 4 5 6 7 8 9 U C Q L A ??

40. Code Tour Remove at 2 capacity = 10 currentSize = 5 list = □ i = 2 1 21 2 3 4 5 6 7 8 9 U C Q L A ??

41. Code Tour Remove at 2 capacity = 10 currentSize = 5 list = □ i = 2 1 21 2 3 4 5 6 7 8 9 U C L A ??

42. Code Tour Remove at 2 capacity = 10 currentSize = 5 list = □ i = 3 1 21 2 3 4 5 6 7 8 9 U C L A ??

43. Code Tour Remove at 2 capacity = 10 currentSize = 4 list = □ 1 2 3 4 51 2 3 4 5 6 7 8 9 U C L A ??

44. Search Search for 'L' Linear search capacity = 10
currentSize = 4 list = □ 1 2 3 4 5 6 7 8 9 U C L A ??

45. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 0 1 2 31 2 3 4 5 6 7 8 9 U C A L ??
currentMin = U
currentMinIndex = 0

46. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 0 j = 11 2 3 4 5 6 7 8 9 U C A L ??
currentMin = U
currentMinIndex = 0

47. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 0 j = 11 2 3 4 5 6 7 8 9 U C A L ??
currentMin = C
currentMinIndex = 1

48. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 0 j = 21 2 3 4 5 6 7 8 9 U C A L ??
currentMin = A
currentMinIndex = 2

49. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 0 j = 31 2 3 4 5 6 7 8 9 U C A L ??
currentMin = A
currentMinIndex = 2

50. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 0 1 2 31 2 3 4 5 6 7 8 9 U C L ??
currentMin = A
currentMinIndex = 3

51. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 0 1 2 31 2 3 4 5 6 7 8 9 A C U L ??
currentMin = A
currentMinIndex = 3

52. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 1 1 2 31 2 3 4 5 6 7 8 9 A C U L ??
currentMin = C
currentMinIndex = 1

53. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 1 j = 21 2 3 4 5 6 7 8 9 A C U L ??
currentMin = C
currentMinIndex = 1

54. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 1 j = 31 2 3 4 5 6 7 8 9 A C U L ??
currentMin = C
currentMinIndex = 1

55. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 1 1 2 31 2 3 4 5 6 7 8 9 A C U L ??
currentMin = C
currentMinIndex = 1

56. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 2 1 2 31 2 3 4 5 6 7 8 9 A C U L ??
currentMin = U
currentMinIndex = 2

57. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 2 j = 31 2 3 4 5 6 7 8 9 A C U L ??
currentMin = L
currentMinIndex = 3

58. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 2 1 2 31 2 3 4 5 6 7 8 9 A C L U ??
currentMin = L
currentMinIndex = 2

59. Sort Selection Sort capacity = 10 currentSize = 4 list = □ i = 2 1 2 31 2 3 4 5 6 7 8 9 A C L U ??
currentMin = L
currentMinIndex = 2