In this article, we will show you, How to write a Python Program to find Sum of Even and Odd Numbers in a List using For Loop, While Loop, and Functions with practical example.

Before you start, please refer List article to understand everything about Lists.

## Python Program to find Sum of Even and Odd Numbers in a List using For Loop

In this python program, we are using For Loop to iterate each and every element in a given List. Inside the loop we are using If statement to check and find Sum of Even and odd numbers.

# Python Program to find Sum of Even and Odd Numbers in a List NumList = [] Even_Sum = 0 Odd_Sum = 0 Number = int(input("Please enter the Total Number of List Elements: ")) for i in range(1, Number + 1): value = int(input("Please enter the Value of %d Element : " %i)) NumList.append(value) for j in range(Number): if(NumList[j] % 2 == 0): Even_Sum = Even_Sum + NumList[j] else: Odd_Sum = Odd_Sum + NumList[j] print("\nThe Sum of Even Numbers in this List = ", Even_Sum) print("The Sum of Odd Numbers in this List = ", Odd_Sum)

**OUTPUT**

**ANALYSIS**

User entered items = [2, 3, 4, 5], Even_Sum = 0, Odd_Sum = 0

**For Loop – First Iteration: **for 0 in range(0, 4)

The condition is True so, compiler will enter into the If Statement

if(NumList[0] % 2 == 0) => if(2 % 2 == 0) – Condition is True

Even_Sum = Even_Sum + NumList[0] => 0 + 2 = 2

**Second Iteration:** for 1 in range(0, 4) – Condition is True

if(NumList[1] % 2 == 0) => if(3 % 2 == 0) – Condition is False

Compiler will enter into the Else block.

Odd_Sum = Odd_Sum + NumList[1] => 0 + 3 = 3

**Third Iteration:** for 2 in range(0, 4) – Condition is True

if(NumList[2] % 2 == 0) => if(4 % 2 == 0) – Condition is True

Even_Sum = 2 + 4 = 6

**Fourth Iteration:** for 3 in range(0, 4) – Condition is True

if(5 % 2 == 0) – Condition is False

Compiler will enter into Else block.

Odd_Sum = 3 + 5 = 8

**Fifth Iteration:** for 4 in range(4) – Condition is False

So compiler will exit from For Loop

## Python Program to find Sum of Even and Odd Numbers in a List using While loop

This program for calculating sum of even and odd numbers is same as above. We just replaced the For Loop with While loop.

# Python Program to find Sum of Even and Odd Numbers in a List NumList = [] Even_Sum = 0 Odd_Sum = 0 j = 0 Number = int(input("Please enter the Total Number of List Elements: ")) for i in range(1, Number + 1): value = int(input("Please enter the Value of %d Element : " %i)) NumList.append(value) while(j < Number): if(NumList[j] % 2 == 0): Even_Sum = Even_Sum + NumList[j] else: Odd_Sum = Odd_Sum + NumList[j] j = j+ 1 print("\nThe Sum of Even Numbers in this List = ", Even_Sum) print("The Sum of Odd Numbers in this List = ", Odd_Sum)

**OUTPUT**

## Python Program to find Sum of Even and Odd Numbers in a List using Functions

This program is same as first example. However, we separated the logic using Functions

# Python Program to find Sum of Even and Odd Numbers in a List def even_sum(NumList): Even_Sum = 0 for j in range(Number): if(NumList[j] % 2 == 0): Even_Sum = Even_Sum + NumList[j] return Even_Sum def odd_sum(NumList): Odd_Sum = 0 for j in range(Number): if(NumList[j] % 2 != 0): Odd_Sum = Odd_Sum + NumList[j] return Odd_Sum NumList = [] Number = int(input("Please enter the Total Number of List Elements: ")) for i in range(1, Number + 1): value = int(input("Please enter the Value of %d Element : " %i)) NumList.append(value) Even_Sum = even_sum(NumList) Odd_Sum = odd_sum(NumList) print("\nThe Sum of Even Numbers in this List = ", Even_Sum) print("The Sum of Odd Numbers in this List = ", Odd_Sum)

**OUTPUT**