12 lines
321 B
Crystal
12 lines
321 B
Crystal
def zigzag(n)
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(seq=(0...n).to_a).cartesian_product(seq)
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.sort_by {|x,y| [x+y, (x+y).even? ? y : -y]}
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.map_with_index{|v, i| {v, i}}.sort.map(&.last).each_slice(n).to_a
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end
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def print_matrix(m)
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format = "%#{m.flatten.max.to_s.size}d " * m[0].size
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m.each {|row| puts format % row}
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end
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print_matrix zigzag(5)
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