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|
TEST_S = <<-EOF
A Y
B X
C Z
EOF
def score(picked_item, outcome)
fail "Wrong picked item '#{picked_item}'" unless picked_item
outcome_score = case outcome
when :win
6
when :draw
3
when :lose
0
end
picked_score = case picked_item
when /A|X/
1
when /B|Y/
2
when /C|Z/
3
end
#puts "#{outcome_score} + #{picked_score}"
return outcome_score + picked_score
end
def guessed_strategy(line)
outcome_map = {
'A X' => :draw,
'A Y' => :win,
'A Z' => :lose,
'B X' => :lose,
'B Y' => :draw,
'B Z' => :win,
'C X' => :win,
'C Y' => :lose,
'C Z' => :draw
}
return outcome_map[line]
end
def correct_strategy(item1, item2)
return :win if item2 == 'Z'
return :draw if item2 == 'Y'
return :lose if item2 == 'X'
end
def what_to_choose(oponent_shape, outcome)
case outcome
when :draw
return oponent_shape
when :win
case oponent_shape
when 'A'
return 'B'
when 'B'
return 'C'
when 'C'
return 'A'
else
fail "Don't know this shape '#{oponent_shape}'"
end
when :lose
case oponent_shape
when 'A'
return 'C'
when 'B'
return 'A'
when 'C'
return 'B'
else
fail "Don't know this shape '#{oponent_shape}'"
end
else
fail "Don't know this outcome '#{outcome}'"
end
end
def part1(filename)
score = 0
File.open(filename) do |f|
scores = f.readlines.map do |line|
item1, item2 = line.chomp.split()
outcome = guessed_strategy(line.chomp)
score(item2, outcome)
end
score = scores.sum
end
score
end
def part2(filename)
score = 0
File.open(filename) do |f|
scores = f.readlines.map do |line|
item1, item2 = line.chomp.split()
outcome = correct_strategy(item1, item2)
shape = what_to_choose(item1, outcome)
score(shape, outcome)
end
score = scores.sum
end
score
end
#puts part1('./day2-test.txt')
#puts part1('./day2.txt')
puts 'Part2'
puts part2('./day2-test.txt')
puts part2('./day2.txt')
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