Comp 271-400 Week 4
Lewis Tower 415, 4:15-8:15
Welcome
Readings:
Bailey chapter 6, sorting: selection sort, insertion
sort, mergesort, quicksort.
Morin chapter 1, sections 1.1 and 1.2
One slight peculiarity of Morin is
that he refers to the array-based List implementation of chapter 2 as an
ArrayStack.
repl.it for C++
1. Speeding up slooow Fibonnaci recursion
with an answer_cache
Answer-cache implementation of Fibonacci(n), in recursion1.zip.
public static long
rfibonacci(int N) {
if (N<=1) return 1;
if rfibonacci(N) is in the answer
cache, return answer_cache[N]
return rfibonacci1(N-2) +
rfibonacci1(N-1); // but put result
into answer_cache[N] first
}
2. Stampchange with an answer_cache
3. expressions
4. TList (in demos)
downcasting
Hashing
Lab 4
Example of a hash dictionary
Chapter 6: Sorting
Radix sort
Trees
binary trees
insertion and search
traversal
tree-based dictionaries