Sum and Prod – Python HackerRank Solution

Problem: Sum and Prod

The sum tool returns the sum of array elements over a given axis.

import numpy

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

print numpy.sum(my_array, axis = 0)         #Output : [4 6]
print numpy.sum(my_array, axis = 1)         #Output : [3 7]
print numpy.sum(my_array, axis = None)      #Output : 10
print numpy.sum(my_array)                   #Output : 10

By default, the axis value is None. Therefore, it performs a sum over all the dimensions of the input array.

prod

The prod tool returns the product of array elements over a given axis.

import numpy

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

print numpy.prod(my_array, axis = 0)            #Output : [3 8]
print numpy.prod(my_array, axis = 1)            #Output : [ 2 12]
print numpy.prod(my_array, axis = None)         #Output : 24
print numpy.prod(my_array)                      #Output : 24

By default, the axis value is None. Therefore, it performs the product over all the dimensions of the input array.

Task

You are given a 2-D array with dimensions NXM.
Your task is to perform the tool over axis 0 and then find the product of that result.

Input Format

The first line of input contains space separated values of N and M.
The next lines contains space separated integers.

Output Format

Compute the sum along axis 0. Then, print the product of that sum.

Sample Input

2 2
1 2
3 4

Sample Output

Explanation

The sum along axis 0= [4 6]
The product of this sum = 24

Code:

import numpy
numpy.set_printoptions(legacy="1.13")

N, M = map(int, input().split())
A = numpy.array([input().split() for _ in range(N)], int)
print(numpy.prod(numpy.sum(A, axis=0), axis=0))

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