mirror of https://github.com/sharkdp/bat.git
57 lines
1.4 KiB
Ruby
57 lines
1.4 KiB
Ruby
class RepeatedSubstring
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def find_repeated_substring(s)
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# catch the edge cases
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return 'NONE' if s == ''
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# check if the string consists of only one character => "aaaaaa" => "a"
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return s.split('').uniq[0] if s.split('').uniq.length == 1
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searched = []
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longest_prefix = 0
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long_prefix = ''
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(0..s.length - 1).each do |i|
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next if searched.include? s[i]
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searched.push(s[i])
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next_occurrences = next_index(s, i + 1, s[i])
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next_occurrences.each do |next_occurrence|
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next if next_occurrence == -1
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prefix = ge_prefix(s[i..next_occurrence - 1], s[next_occurrence..s.length])
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if prefix.length > longest_prefix
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longest_prefix = prefix.length
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long_prefix = prefix
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end
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end
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end
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# if prefix == " " it is a invalid sequence
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return 'NONE' if long_prefix.strip.empty?
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long_prefix
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end
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def get_prefix(s1, s2)
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prefix = ''
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min_length = [s1.length, s2.length].min
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return '' if s1.nil? || s2.nil?
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(0..min_length - 1).each do |i|
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return prefix if s1[i] != s2[i]
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prefix += s1[i]
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end
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prefix
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end
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def next_index(seq, index, value)
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indexes = []
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(index..seq.length).each do |i|
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indexes.push(i) if seq[i] == value
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end
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indexes
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end
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def find_repeated_substring_file(file_path)
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File.open(file_path).read.each_line.map { |line| find_repeated_substring(line) }
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end
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end
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