Count Even and Odd Numbers from List in Python

In this example, you will find and count odd/even numbers from list.

Example 1: Using Loop

    
# Python program to count even and odd number using loop

list1 = [1,2,3,4,5,6,7,8,9]
  
even_count, odd_count = 0, 0
num = 0
  
# using while loop
while(num < len(list1)):
    if list1[num] % 2 == 0:
        even_count += 1
    else:
        odd_count += 1

    num += 1
    
print("Even numbers in the list: ", even_count)
print("Odd numbers in the list: ", odd_count)
       

Output :

    
Even numbers in the list:  4
Odd numbers in the list:  5
    

Explanation :

The logic of the program is simple, we iterate through each element of the list and check its remainder after dividing by 2. If the remainder is 0 then it is even number so we increment even counter, else it is an odd number and we increment the odd counter.

Example 2: Using Lambda

    
# Python program to count even and odd number using lambda function
list1 = [1,2,3,4,5,6,7,8,9]

even_count = list(filter(lambda x: (x % 2 == 0), list1))
odd_count = list(filter(lambda x: (x % 2 != 0), list1)) 

print("Even numbers in the list: ", len(even_count))
print("Odd numbers in the list: ", len(odd_count))
       

Output :

    
Even numbers in the list:  4
Odd numbers in the list:  5
    

Explanation :

Lambda functions are anonymous functions which are kind of instant run functions. Here, we create two separate even and odd list using filter function count the length of each.

Example 3: Using List Comprehension

    
# Python program to count even and odd number using list comprehension
list1 = [1,2,3,4,5,6,7,8,9]

only_odd = [num for num in list1 if num % 2 == 1]
odd_count = len(only_odd)

print("Even numbers in the list: ", len(list1) - odd_count)
print("Odd numbers in the list: ", odd_count)
       

Output :

    
Even numbers in the list:  4
Odd numbers in the list:  5
    

Explanation :

Here, create a new list be selecting only even elements. At last, we count the elements to get even numbers in the list and calculate odd numbers count.