EECS 281, Week 3: Monday

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EECS 281, Week 3: Monday STL Containers Type Containers vector, deque, list, forward list (multi)set, (multi)map unordered_(multi)set, unordered_(multi)map queue, stack, priority queue Vector Deque Vector vs. Deque? Array Maxim Aleksa ([email protected]) 0 < !5 http://maximal.io/eecs281 EECS 281, Week 3: Monday List Forward List Iterator Invalidation Vector ______________________________________________________________________________ Deque ______________________________________________________________________________ List ______________________________________________________________________________ Sequence Containers Summary Container insert/remove front insert/remove middle insert/remove back search Vector Deque Array List Forward List Associative Containers Set Multiset Map Multipap Unordered Associative Containers Unordered set Unordered multiset Unordered map Unordered multipap Maxim Aleksa ([email protected]) 4 < !5 http://maximal.io/eecs281 EECS 281, Week 3: Monday Priority Queue Heap The (binary) heap data structure is an array that represents a nearly complete binary tree. 0 16 1 14 2 10 3 4 5 6 8 7 9 3 7 8 9 2 4 1 Heap property Max-heap property: _________________________________________________________________ Min-heap property: _________________________________________________________________ Heap as an array Number of elements: _________________________________________________________________ root(): ________________________________________________________________________ parent(i): ________________________________________________________________________ left(i): ________________________________________________________________________ right(i): ________________________________________________________________________ height(): ________________________________________________________________________ Heap operations buildMaxHeap produce a max-heap from an unordered array maxHeapify(i) correct a single violation of the heap property in a subtree with root at i maxElement return the largest element removeMaxElement remove the largest element increaseKey(i, k) update the key of an element to a larger value k insert(k) add an element with key k Maxim Aleksa ([email protected]) 5 < !5 http://maximal.io/eecs281 EECS 281, Week 3: Monday maxHeapify 16 4 10 14 7 9 3 2 8 1 buildMaxHeap 4 1 3 2 16 9 10 14 8 7 maxElement removeMaxElement 16 14 10 8 7 9 3 2 4 1 insert 14 8 10 4 7 9 3 2 1 Maxim Aleksa ([email protected]) 6 < !5 http://maximal.io/eecs281 EECS 281, Week 3: Monday Queue with Stacks Implement NewQueue, a templated class that represents a queue using two stacks. Speciﬁcally, implement at least the following member functions: • size(), which should return the size of the queue • empty(), which should return true if the queue is empty and false otherwise • push(), which should insert an element at the “end” of the queue • pop(), which should remove an element from the “front” of the queue Feel free to use std::stack that has the same methods: size(), empty(), push() and pop(). When ﬁnished, take a picture of your code and email it to Maxim. Use additional pages if needed. Maxim Aleksa ([email protected]) 6 < !5 http://maximal.io/eecs281.

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An Alternative to Fibonacci Heaps with Worst Case Rather Than Amortized Time Bounds∗
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