1. 15-111 Advanced Programming
Mid Term Review
15-111
Advanced Programming
Ananda Gunawardena
8/2/2018

2. Midterm Topics Lists – Arrays and Linked Lists Basic Java Constructs
Singly, doubly, circular, Multilinked Lists
Complexity of Algorithms
Interfaces
Strings
Recursion
8/2/2018

3. What to Bring to test One page of Notes – both sides ok
No computers or PDA’s
Pencil and Eraser
You can access Java API
Some memory
8/2/2018

4. Arrays
Using ArrayList API methods complete the following method that returns true if there are duplicates in the array A of Comparables
public boolean duplicates(ArrayList A) }
8/2/2018

5. Complexity
Determine the complexity of the following algorithms using O(1), O(n), O(log n) and O(n2). Justify your answer in each case.
Printing a linked list of size n
Printing a singly linked list of size n in reverse
Finding the largest entry on a sorted list
Making a non-circular linked list circular
Reversing a linked list
8/2/2018

6. Linked Lists
Suppose L is a linked list of size at least 2, the references to two adjacent nodes are given by N and M. Write one (or may be two) lines of code to accomplish the following. Assume Node class has two public fields, data (Comparable) and next(Node)
Insert a new Node O between N and M
Insert a new Node O after M
Delete the nodes N and M
Move the node M to the beginning of the list
8/2/2018

7. Recursion
What is the output given by following recursive function if foo(4) is called?
Public void foo(int n) {
if (n>0){
foo(n-1);
System.out.println(n); }
8/2/2018

8. Debugging public int sum(int n){ int i=0; while (i<=n){ int sum=0;
What is wrong with the following code? (if any). The method is supposed to find the sum = 1+2+…+n
public int sum(int n){
int i=0;
while (i<=n){
int sum=0;
sum += ++I; }
return sum;
8/2/2018

9. Doubly Linked Lists
Assume M is a node in a doubly linked list. Assume we have next and prev references. Write the code to
Swap M and its successor (assume M has a non-null successor)
Insert M to the beginning of the list
8/2/2018

10. ArrayLists
Suppose A is an ArrayList of comparables. Write the code to find the max of A
8/2/2018

11. Arrays vs Linked Lists List two advantages of Arrays over Linked Lists
8/2/2018

12. Arrays vs Linked Lists List two advantages of Linked Lists over Arrays
8/2/2018

13. Strings
Using String API methods, reverse a String S
8/2/2018

14. Recursion
Write a recursive definition that returns the number of 1s in the binary representation of N. Use the fact that this number equals the number of 1s in the representation of N/2, plus 1, if N is odd.
8/2/2018

15. Complexity What are the time complexities of the following loops?
(a) for (i=0;i<n;i++)
for (j=0; j<n; j \= 2) { something}
(b) for (i=0; i<n; i++)
swap(A[i],A[n-i-1])
8/2/2018