calculate the total number of odd elements in a list

try using modulo and list comprehension

arr=[13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735]

def odd_elements(arr):
    return len([x for x in arr if x % 2 != 0])

print(odd_elements(arr))

or, using sum()

arr=[13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735]


def odd_elements(arr):
    return sum(1 for i in arr if i % 2)

print(odd_elements(arr))

You cannot call sum on an int (num). You can do the following:

arr = [13, 15, 4, 6, 8, 71, 45, 54, 56, 77, 67, 88, 49, 33838, 3784376, 77735] 
count = 0
for num in arr:
  if num % 2 != 0:
    count += 1
    print(count)

or more simply:

print(sum(num % 2 == 1 for num in arr))

You can do with list comprehension,

In [1]: sum([i for i in arr if i %2 != 0])
Out[1]: 78072

And, sum(int) is not possible because sum only takes iterable (list, tuple, etc.) as the argument.

sum only accepts iterables, not single items.

try this:

a = a + num

take a look at this link to learn more about sum.

You need to remove a = sum(num). sum() takes an array but you have given it a int.

The code should be like this:

total = 0
arr=[13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735] 
for num in arr:
  if num % 2 != 0:
    total = total + 1
print(total)

You are looping over the list, thus num is the current element in the iteration. You want to use sum on an iterable such as below:

> arr = [13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735]
> sum(num % 2 == 0 for num in arr)
8

I think you can get them with a list comprehension:

arr=[13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735]
elems = sum([ 1 if num %2 != 0 else 0 for num in arr])
print(f"Number of odd elements: {elems}")

Checkout as you are trying to sum the value of the "num" itself. Not sure if you were trying to append it to a list onto a.

im no sure what you mean by total number of odd elements as in all the times theres a odd number or the sum of all the odd numbers but here

arr=[13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735] 
a = 0
for num in arr:
  if num % 2 != 0:
    a += num
print(a)

sum is used on lists so if you realy wanted to use the sum it looks like this

arr=[13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735] 
a = []
for num in arr:
  if num % 2 != 0:
    a.append(num)
print(sum(a))

The sum function takes a list as an argument and sums all the numbers inside that list.
Instead of passing a list, you passed an integer (at line 4):

a=sum(num)

num is an integer, not a list.
What you might want to do to count the number of odd numbers in a list is this:

odd_numbers_count = 0 #keeps track of how many odd numbers there are
arr=[13,15,4,6,8,71,45,54,56,77,67,88,49,33838,3784376,77735] 
for num in arr:
  if num % 2 != 0:
    odd_numbers_count += 1 # every time you encounter an odd number, it adds one to the count
print(f'Total number of odd elements: {odd_numbers_count}')