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Matrix Multiplication From Scratch
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Matrix Multiplication From Scratch

MediumPython

Problem

Implement a function to perform matrix multiplication from scratch. Use the signature matrix_multiply(A, B), where A and B are non-empty rectangular lists of numbers, and return a new matrix containing their product without modifying either input. If A has shape m x n, B must have shape n x p, and the result has shape m x p; for example, [[1, 2]] multiplied by [[3], [4]] returns [[11]].

Constraints

  • A and B are non-empty rectangular matrices represented as lists of lists.
  • If A has shape m x n, B has shape n x p.
  • 1 <= m, n, p <= 100
  • Matrix entries are integers in the range -10^9 to 10^9.
  • Return a new matrix and do not modify A or B.

Function Signature

def matrix_multiply(A, B):
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