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21 lines
333 B
Ruby
21 lines
333 B
Ruby
# @param {Integer} num_rows
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# @return {Integer[][]}
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# 1
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# 1 1
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# 1 2 1
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# 1 3 3 1
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def pascals_triangle(num_rows)
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rows = [[1], [1, 1]]
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while rows.count < num_rows
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new_row = [1]
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rows.last.each_cons(2) { |first, second| new_row << first + second }
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new_row << 1
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rows << new_row
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end
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rows[0...num_rows]
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end
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