Rosetta Code

Matrix multiplication

Multiply two small matrices.

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Sourcerosettacode/popular/matrix_multiplication.vibe
def matrix_multiply(left: array<array<int>>, right: array<array<int>>) -> array<array<int>>
  product: array<array<int>> = []
  row_index = 0

  while row_index < left.length
    row: array<int> = []
    column_index = 0

    while column_index < right.fetch(0).length
      total = 0
      inner_index = 0

      while inner_index < right.length
        total = total + (left.fetch(row_index).fetch(inner_index) * right.fetch(inner_index).fetch(column_index))
        inner_index = inner_index + 1
      end

      row.push(total)
      column_index = column_index + 1
    end

    product.push(row)
    row_index = row_index + 1
  end

  product
end

def run -> array<array<int>>
  left = [
    [1, 2, 3],
    [4, 5, 6]
  ]

  right = [
    [7, 8],
    [9, 10],
    [11, 12]
  ]

  matrix_multiply(left, right)
end

Output

Click Run example to see the result.

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