cos418_hw1_1

README

COS418 Assignment 1 (Part 1): Intro to Go

Introduction

In this assignment you will solve two short problems as a way to familiarize yourself with the Go programming language. We expect you to already have a basic knowledge of the language. If you're starting from nothing, we highly recommend going through the Golang tour before you begin this assignment.

Software

You will find the code in the same directory as this readme. The two problems that you need to solve are in q1.go and q2.go. You should only add code to places that say TODO: implement me. Do not change any of the function signatures as our testing framework uses them.

Q1 - Top K words: The task is to find the K most common words in a given document. To exclude common words such as "a" and "the", the user of your program should be able to specify the minimum character threshold for a word. Word matching is case insensitive and punctuation should be removed. You can find more details on what qualifies as a word in the comments in the code.

Q2 - Parallel sum: The task is to implement a function that sums a list of numbers in a file in parallel. For this problem you are required to use goroutines (the go keyword) and channels to pass messages across the goroutines. While it is possible to just sum all the numbers sequentially, the point of this problem is to familiarize yourself with the synchronization mechanisms in Go.

Testing

Our grading uses the tests in q1_test.go and q2_test.go provided to you. To test the correctness of your code, run the following:

  $ cd assignment1-1
  $ go test

If all tests pass, you should see the following output:

  $ go test
  PASS
  ok      /path/to/assignment1-1   0.009s

Point Distribution

Test	Points
Q1Simple	4
Q1DeclarationOfIndependence	4
Q2_1	3
Q2_2	3
Q2_3	3
Q2_4	3

Submitting Assignment

Now you need to submit your assignment. Commit your change and push it to the remote repository by doing the following:

$ git commit -am "[you fill me in]"
$ git tag -a -m "i finished assignment 1-1" a11-handin
$ git push origin master
$ git push origin a11-handin

Please fill in this google form with your GitHub username and your Princeton NetID. This allows us to map your GitHub to your Princeton information for grading. We'll run the grading scripts daily and send your grading information to your Princeton email.

In order to overwrite a tag use the force flag as follows.

$ git tag -fam "i finished assignment 1-1" a11-handin
$ git push -f --tags

Documentation

Index

• type WordCount
  • func (wc WordCount) String() string

Types

type WordCount

type WordCount struct {
	Word  string
	Count int
}

A struct that represents how many times a word is observed in a document

func (WordCount) String

func (wc WordCount) String() string