HackerRank Python Solution - Numpy Topic - Dot and Cross

Dot:

The dot tool returns the dot product of two arrays.

import numpy

A = numpy.array([ 1, 2 ])
B = numpy.array([ 3, 4 ])

print numpy.dot(A, B)       #Output : 11

Cross:

The cross tool returns the cross product of two arrays.

import numpy

A = numpy.array([ 1, 2 ])
B = numpy.array([ 3, 4 ])

print numpy.cross(A, B)     #Output : -2

Task:

You are given two arrays A and B. Both have dimensions of N x N. Your task is to compute their matrix product.

Input Format: 

The first line contains the integer N. The next N lines contain N space-separated integers of array A. The following N lines contain N space-separated integers of array B.

Output Format:

Print the matrix multiplication of A and B.

Sample Input:

2
1 2
3 4
1 2
3 4

Sample Output:

[[ 7 10]
 [15 22]]

Solution:

import numpy as np

n = int(input())

arr = [list(map(int,input().split())) for _ in range(n)]
arr2 = [list(map(int,input().split())) for _ in range(n)]
print(np.dot(arr,arr2))

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