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Published at Sep 27 2020
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Instructions

Test suite

Solution

Tally the results of a small football competition.

Based on an input file containing which team played against which and what the outcome was, create a file with a table like this:

```
Team | MP | W | D | L | P
Devastating Donkeys | 3 | 2 | 1 | 0 | 7
Allegoric Alaskans | 3 | 2 | 0 | 1 | 6
Blithering Badgers | 3 | 1 | 0 | 2 | 3
Courageous Californians | 3 | 0 | 1 | 2 | 1
```

What do those abbreviations mean?

- MP: Matches Played
- W: Matches Won
- D: Matches Drawn (Tied)
- L: Matches Lost
- P: Points

A win earns a team 3 points. A draw earns 1. A loss earns 0.

The outcome should be ordered by points, descending. In case of a tie, teams are ordered alphabetically.

Input

Your tallying program will receive input that looks like:

```
Allegoric Alaskans;Blithering Badgers;win
Devastating Donkeys;Courageous Californians;draw
Devastating Donkeys;Allegoric Alaskans;win
Courageous Californians;Blithering Badgers;loss
Blithering Badgers;Devastating Donkeys;loss
Allegoric Alaskans;Courageous Californians;win
```

The result of the match refers to the first team listed. So this line

```
Allegoric Alaskans;Blithering Badgers;win
```

Means that the Allegoric Alaskans beat the Blithering Badgers.

This line:

```
Courageous Californians;Blithering Badgers;loss
```

Means that the Blithering Badgers beat the Courageous Californians.

And this line:

```
Devastating Donkeys;Courageous Californians;draw
```

Means that the Devastating Donkeys and Courageous Californians tied.

For installation and learning resources, refer to the Ruby resources page.

For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest:

```
gem install minitest
```

If you would like color output, you can `require 'minitest/pride'`

in
the test file, or note the alternative instruction, below, for running
the test file.

Run the tests from the exercise directory using the following command:

```
ruby tournament_test.rb
```

To include color from the command line:

```
ruby -r minitest/pride tournament_test.rb
```

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

```
require 'minitest/autorun'
require_relative 'tournament'
# Common test data version: 1.4.0 ee01fe0
class TournamentTest < Minitest::Test
def test_just_the_header_if_no_input
# skip
input = <<~INPUT
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_a_win_is_three_points_a_loss_is_zero_points
skip
input = <<~INPUT
Allegoric Alaskans;Blithering Badgers;win
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 1 | 1 | 0 | 0 | 3
Blithering Badgers | 1 | 0 | 0 | 1 | 0
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_a_win_can_also_be_expressed_as_a_loss
skip
input = <<~INPUT
Blithering Badgers;Allegoric Alaskans;loss
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 1 | 1 | 0 | 0 | 3
Blithering Badgers | 1 | 0 | 0 | 1 | 0
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_a_different_team_can_win
skip
input = <<~INPUT
Blithering Badgers;Allegoric Alaskans;win
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Blithering Badgers | 1 | 1 | 0 | 0 | 3
Allegoric Alaskans | 1 | 0 | 0 | 1 | 0
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_a_draw_is_one_point_each
skip
input = <<~INPUT
Allegoric Alaskans;Blithering Badgers;draw
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 1 | 0 | 1 | 0 | 1
Blithering Badgers | 1 | 0 | 1 | 0 | 1
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_there_can_be_more_than_one_match
skip
input = <<~INPUT
Allegoric Alaskans;Blithering Badgers;win
Allegoric Alaskans;Blithering Badgers;win
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 2 | 2 | 0 | 0 | 6
Blithering Badgers | 2 | 0 | 0 | 2 | 0
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_there_can_be_more_than_one_winner
skip
input = <<~INPUT
Allegoric Alaskans;Blithering Badgers;loss
Allegoric Alaskans;Blithering Badgers;win
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 2 | 1 | 0 | 1 | 3
Blithering Badgers | 2 | 1 | 0 | 1 | 3
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_there_can_be_more_than_two_teams
skip
input = <<~INPUT
Allegoric Alaskans;Blithering Badgers;win
Blithering Badgers;Courageous Californians;win
Courageous Californians;Allegoric Alaskans;loss
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 2 | 2 | 0 | 0 | 6
Blithering Badgers | 2 | 1 | 0 | 1 | 3
Courageous Californians | 2 | 0 | 0 | 2 | 0
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_typical_input
skip
input = <<~INPUT
Allegoric Alaskans;Blithering Badgers;win
Devastating Donkeys;Courageous Californians;draw
Devastating Donkeys;Allegoric Alaskans;win
Courageous Californians;Blithering Badgers;loss
Blithering Badgers;Devastating Donkeys;loss
Allegoric Alaskans;Courageous Californians;win
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Devastating Donkeys | 3 | 2 | 1 | 0 | 7
Allegoric Alaskans | 3 | 2 | 0 | 1 | 6
Blithering Badgers | 3 | 1 | 0 | 2 | 3
Courageous Californians | 3 | 0 | 1 | 2 | 1
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_incomplete_competition_not_all_pairs_have_played
skip
input = <<~INPUT
Allegoric Alaskans;Blithering Badgers;loss
Devastating Donkeys;Allegoric Alaskans;loss
Courageous Californians;Blithering Badgers;draw
Allegoric Alaskans;Courageous Californians;win
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 3 | 2 | 0 | 1 | 6
Blithering Badgers | 2 | 1 | 1 | 0 | 4
Courageous Californians | 2 | 0 | 1 | 1 | 1
Devastating Donkeys | 1 | 0 | 0 | 1 | 0
TALLY
assert_equal expected, Tournament.tally(input)
end
def test_ties_broken_alphabetically
skip
input = <<~INPUT
Courageous Californians;Devastating Donkeys;win
Allegoric Alaskans;Blithering Badgers;win
Devastating Donkeys;Allegoric Alaskans;loss
Courageous Californians;Blithering Badgers;win
Blithering Badgers;Devastating Donkeys;draw
Allegoric Alaskans;Courageous Californians;draw
INPUT
expected = <<~TALLY
Team | MP | W | D | L | P
Allegoric Alaskans | 3 | 2 | 1 | 0 | 7
Courageous Californians | 3 | 2 | 1 | 0 | 7
Blithering Badgers | 3 | 0 | 1 | 2 | 1
Devastating Donkeys | 3 | 0 | 1 | 2 | 1
TALLY
assert_equal expected, Tournament.tally(input)
end
end
```

```
class Tournament
Header = '%-31s| MP | W | D | L | P' % 'Team'
Reciprocal = {'win' => 'loss', 'draw' => 'draw', 'loss' => 'win'}
def self.tally(input)
new(input).tally
end
private
attr_accessor :data, :matches, :teams, :stats
def initialize(input)
@data = input.lines.map(&:chomp).map { |line| line.split(';') }
@matches = Hash.new {[]}
@teams = {}
@stats = {}
add_matches
end
def add_matches
data.map do |team_A, team_B, score|
matches[team_A] += [score]
matches[team_B] += [Reciprocal[score]]
end
end
def create_statistics
teams.each do |name, scores|
%w[win draw loss].each { |state| scores[state] = 0 unless scores[state] }
win = scores['win']
draw = scores['draw']
loss = scores['loss']
matches = win + draw + loss
points = (win * 3) + draw
stats.merge!(name => { name: name, matches: matches, win: win, draw: draw, loss: loss, points: points })
end
end
def report
Header + "\n" +
stats.values
.sort_by { |scores| [-scores[:points], scores[:name]] }
.map do |sorted|
"%-30s | %2d | %2d | %2d | %2d | %2d\n" %
[
sorted[:name],
sorted[:matches],
sorted[:win],
sorted[:draw],
sorted[:loss],
sorted[:points]
]
end.join
end
public
def tally
matches.each { |name, scores| teams.merge!({ name => scores.tally }) }
create_statistics
to_s
end
def to_s
teams.include?(nil) ? Header + "\n" : report
end
end
```

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