1. Programming Midterm Review
CSCI2100B
Data Structure

2. Background CUHK has a strong tradition in ACM ICPC Excellent Tutors
8th in the world in 2000
8th in the world in 2011
Many regional and world final appearances
Excellent Tutors
6 weeks to set the questions
Weeks for the preparation of the system
1 day to copy the hard disks
Additional hours

3. Exam Statistics Number of Participants: 78
All participants solved at least 1 problem!!!
One participant solved all 7 problems!!!
Average number of solved problems: 2.15
Average time (penalty): 183
Total attempts per participant: 7.9

4. Exam Statistics Number of solved problems: 7 – 1 participant
5 – 1 participant (1 non-CSE major)
4 – 2 participants (1 non-CSE major)
3 – 13 participants (1 non-CSE major)
2 – 48 participants (6 non-CSE major)
1 – 13 participants (2 non-CSE major)

5. Exam Statistics Acceptance rate for each Problem: A – 77/134 (57.46%)
D – 4/25 (16.00%)
E – 16/48 (33.33%)
F – 2/40 (5.00%)
G – 1/2 (50.00%)
This is interesting. According to this statistics, the order of problem should be: A B E D F C G

6. Prize Championship: 1st Runner-up: 2nd Runner-up Honorable Mention:
CHAN, Pak Hay ( )
1st Runner-up:
LAM, Ka Ho ( )
2nd Runner-up
YU, Chun Lung ( )
Honorable Mention:
PANG Yui Tik ( )
WAN, Ka Ki ( )

7. Prize Best Female Coder: Honorable Mention: CHU, Wing Yin (1155030760)
DERMAWAN, Teresa ( )

8. Prize Best Non-CSE Coder: Honorable Mention: Most Effective Coder:
LAM, Ka Ho ( )
Honorable Mention:
PANG, Yui Tik ( )
Most Effective Coder:

9. Miscellaneous Extra credit problem Looking for summer interns
Internet/Web development
Mobile development

10. Problem Review

11. A – String Revision

12. B – Intersection of Two Arrays
Best solution: O(m+n)
m – the length of array A
n – the length of array B

13. C – Stone Piles http://acm.timus.ru/problem.aspx?num=1005
Brute force can satisfy the time limit

14. D – Prime Palindromes USACO 1.5.2
USACO Training Program curriculum is one of the best paths to learn data structures and algorithms.

15. E – Train Re-arrangement II
Adapted from homework
Algorithm is the same, only need to change stack functions to queue functions

16. F – Fruit Merge II Adapted from homework
Use two queues, one for original fruit piles, the other for newly combined fruit piles
Every time, choose two smallest numbers from the two queues

17. G – Counting Factor Trees
Dynamic Programming