Question

I want to ask a question about course 2008 fall .The question is in Set 6 problem #3.
"Next, change the implementation of is_valid_word to take as an argument the representation you created above rather than the word_list itself. Remember that the choice of representation can have a big impact on performance. This modification will improve the complexity of is_valid_word from O(len(word_list)) to O(1)." I can't understand how can we fulfill this change and do not know why it changes the complexity to O(1).

Answer 1

The pdf's link is here: http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-00-introduction-to-computer-science-and-programming-fall-2008/assignments/pset6.pdf

Answer 2

how did you implement is_valid_word using word_list? why is its complexity O(len(word_list))?

how will you implement is_valid_word with the new representation of the wordlist?

http://wiki.python.org/moin/TimeComplexity

Answer 3

President Johnson and Congress fought over who would be in control of Reconstruction.

Answer 4

After Pennsylvania experienced its oil boom in 1859, three other states discovered vast oil reserves.

Answer 5

Compute the requested average.

Tim Worker wants to purchase an automobile warranty costing $856.

Answer 6

What does LMAO mean?

Answer 7

u0394RST is dilated about the origin, O, to create u0394R'S'T'. Point R is located at (3, 9), and point R' is located at (1.

Answer 8

A swimming pool is 72.25 feet long and 51.5 feet wide. How much longer is the pool than it is wide?

20.

Answer 9

What was one result of the GI Bill?

Answer 10

For some jobs, the rate will be set by a minimum specified in the Fair Labor Standards Act.

Answer 11

g

Answer 12

People in opposition to multiculturalism believe it: ________. Select all that apply.

Answer 13

Victoria enjoys dance class; all girls enjoy dance class
what is the fallacy

Answer 14

Those people who favor allowing or increasing immigration levels state that newly arrived immigrants: _________.

Answer 15

In right triangle ABC,

Answer 16

What two universities did Barack Obama graduate from? Select all that apply.

Har

Answer 17

Which of the following is the most likely reason the writers of the Constitution did NOT define American citizenship?

They could not agree on a definition.

Answer 18

Math help!

Answer 19

In the diagram, u0394JKL ~ u0394MNO. What is the length of side KL?

Answer 20

Shortly after taking office, President Obama pushed through a ____ billion dollar stimulus package to get America back on its feet.

Answer 21

The Homestead Act (1862) was an example of:

a push factor
a survival tactic
a ci

Answer 22

What is the purpose of international trade?

to exchange goods and services in a