python

Question

What is the output of this code ?

l = [x for x in range(1,5)]
f = [2 if x % 2 else 1 for x in l]
n= [x*s for x,s in zip(l,f)]
print(sum(n))

Output: 14

why 14 ?

Answer 1

print each list

l = [x for x in range(1,5)]
print(l)
f = [2 if x % 2 else 1 for x in l]
print(f)
n= [x*s for x,s in zip(l,f)]
print(n)
print(sum(n))

l is list of numbers from 1, 2, 3, 4.
f is 2, 1, 2, 1 because in the list comprehension, it will append 2 if the number is odd and 1 if even for x in l. (odd, x%2==1 is True, so 2 is appended, else 1)
n is just the product of the items of list l and f with the same index. (zip function)

Answer 2

l = [ 1,2,3,4 ] #range(1, 5)
f = [ 2,1,2,1 ] # odd 2, even 1
n = [ 1*2 , 2*1, 3*2, 4*1 ] = [ 2, 2, 6, 4 ] #zip(l, f)
sum(n) => 2+2+6+4= 14

Answer 3

Thanks 🙏