Our task is to print all even numbers within a given range. The simplest way to achieve this is by using a loop to iterate through the range and check each number for evenness. Let's explore some methods to do so.

Using Loop

We can use a for loop with if conditional to check if a number is even.

s = 1
e = 10

for i in range(s, e + 1):
    if i % 2 == 0:
        print(i)

2
4
6
8
10

Explanation:

• We loop through all the numbers in the given range (s to e).
• The condition i % 2 == 0 checks if the number is even (i.e., divisible by 2).
• If the condition is True than print the number.

Using List Comprehension

List comprehension provides a concise way to filter even numbers and print them directly.

s = 1
e = 10

res = [i for i in range(s, e + 1) if i % 2 == 0]
print(res)

[2, 4, 6, 8, 10]

Explanation:

• This list comprehension generates a list of numbers from s to e where i % 2 == 0 (i.e., the number is even).
• The result is a list of even numbers which is then printed.

Using range() with Step

The built-in range() function can also be used efficiently to print even numbers by setting a step value of 2. This avoids the need for an extra if condition.

s = 1
e = 10

for i in range(2, e + 1, 2):
    print(i)

2
4
6
8
10

Explanation:

• The range(2, e+ 1, 2) generates numbers starting from 2 and increments by 2, this producing only even numbers.
• No need for an if condition as the range is already defined to only include even numbers.

Related Articles:

• Python For Loops
• List Comprehension in Python
• Python range() function