Zimmer
CSCI 270
Spring 042
Assignment #3
Due Date: March 31, 2004
Remember you are to complete the assignment on your own, unless otherwise stated. Make sure
you follow the Assignment Guidelines you received at the beginning of the semester.
For the assignment below turn in:

Complete the questions below – write/type on one side of the page only, make sure your
work is legible. Attach this assignment sheet as the cover sheet placing your name,
csci270-001, and A#3 on three lines in the upper right corner. In the upper left corner
staple the purple cover to your answers.
Complete the following:
1. List and define three major search strategies
2. Define blind searching and list an advantage and a disadvantage of this search technique.
3. Define heuristic searching and give an advantage and a disadvantage of this search technique.
4. Define forward chaining and give an example of a problem that would use it.
5. Define backward chaining and give an example of a problem that would use it.
6. Study the search tree below. The number associated with each node indicates the profit
associated with that node. The goal is to find a node with the profit value of twenty or
higher.
1
Zimmer
CSCI 270
Spring 042
7. Apply the best-first approach to the traveling sales person problem below. The number
on each arc indicates the distance. Start from city 5.
8. Your mission is to process three jobs on one machine (one after the other) with the least
possible change-over time. The machine is currently empty. The table below shows you
how long it takes, in minutes, to change from one job (or from empty) to another. Draw
the entire search tree using empty as the starting position. Write the sequence using the
best-first approach.
To Job
From Job
1
2
3
Empty
25
20
30
1
0
35
20
2
50
0
20
3
45
10
0
2
Zimmer
CSCI 270
Spring 042
9. The table below shows a doctor’s patients who are waiting for their appointments, and the
corresponding projected treatment times. The doctor wishes to schedule the patients to
minimize average wait time. Formulate two heuristic rules (use English) and compare
them with taking the patients in the order given (A, B, C, …, F).
Patient
Treatment Time in hours
A
1.0
B
.2
C
2.0
D
1.5
E
.1
F
.7
3