37 lines
773 B
Ruby
Executable File
37 lines
773 B
Ruby
Executable File
#!/usr/bin/env ruby
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def letter_pairs_count(input)
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characters = input
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.each_char
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.each_cons(4)
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.reject { |(a, b, c, d)| (a == b && b == c || b == c && c == d ) && a != d }
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last_index = characters.size
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pairs = characters
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.flat_map
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.with_index(1) { |(a, b, c, d), i| i == last_index ? [a+b, b+c, c+d] : [a+b] }
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pairs.tally.values.max || 0
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end
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def surrounded_letter_count(input)
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input
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.each_char
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.each_cons(3)
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.count { |(a, _, b)| a == b }
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end
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def is_really_nice?(input)
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return false if input.empty?
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return false if letter_pairs_count(input) < 2
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return false if surrounded_letter_count(input).zero?
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true
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end
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result = File.readlines(ARGV.first, chomp: true).sum do |line|
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is_really_nice?(line) ? 1 : 0
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end
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puts result
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