41 lines
792 B
Ruby
41 lines
792 B
Ruby
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# Naive bruteforce solution
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# @param {Integer} n
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# @return {String[]}
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def generate_parenthesis(n)
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combinations = ['(']
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# Generate an array of all possible combinations
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(2..n * 2).each do |i|
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new_iteration = []
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combinations.each do |elem|
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new_iteration.push("#{elem})")
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# Opening bracket can't be the last one
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new_iteration.push("#{elem}(") if i != n * 2
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end
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combinations = new_iteration
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end
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# Return only valid combinations
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combinations.select { |l| parenthesis_valid?(l) }
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end
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def parenthesis_valid?(s)
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open_brackets = 0
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s.each_char do |char|
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if char == '('
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open_brackets += 1
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else
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open_brackets -= 1
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end
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return false if open_brackets.negative?
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end
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return false if open_brackets.positive?
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true
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end
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