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Sayandeep Majumdar
Sayandeep Majumdar

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Mastering Python Loops

Introduction:

Loops play a vital role in repetitive execution of code blocks, allowing developers to automate tasks and process large sets of data efficiently. In this blog post, we will explore the two main types of loops in Python: "for" and "while" loops. We'll dive into their syntax, discuss their applications, and provide examples to demonstrate their usage. Let's get started!

1. The "for" Loop:

The "for" loop in Python allows you to iterate over a sequence of elements, such as lists, tuples, strings, or even ranges. It follows a specific syntax:

for element in sequence:
    # Code block to be executed

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Example 1: Iterating over a list

fruits = ["apple", "banana", "orange"]
for fruit in fruits:
    print(fruit)

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Output:

apple
banana
orange

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Example 2: Iterating over a string

message = "Hello, world!"
for char in message:
    print(char)

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Output:

H
e
l
l
o
,

w
o
r
l
d
!

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2. The "while" Loop:

The "while" loop in Python repeatedly executes a block of code as long as a specified condition is true. It follows this syntax:

while condition:
    # Code block to be executed

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Example 1: Counting from 1 to 5

count = 1
while count <= 5:
    print(count)
    count += 1

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Output:

1
2
3
4
5

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Example 2: Summing numbers until a condition is met

total = 0
num = 1
while total < 10:
    total += num
    num += 1
print("Sum:", total)

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Output:

Sum: 10

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3. Controlling Loop Flow:

Within loops, certain statements can alter the flow of execution. These statements include "break," which terminates the loop prematurely, and "continue," which skips the current iteration and proceeds to the next one.

Example 1: Using "break" in a "for" loop

fruits = ["apple", "banana", "orange"]
for fruit in fruits:
    if fruit == "banana":
        break
    print(fruit)

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Output:

apple

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Example 2: Using "continue" in a "while" loop

count = 0
while count < 5:
    count += 1
    if count == 3:
        continue
    print(count)

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Output:

1
2
4
5

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Conclusion:

Loops are indispensable constructs in Python programming, enabling repetitive tasks to be executed with ease. In this blog post, we explored the "for" and "while" loops, along with their syntax and applications. By leveraging these loops and understanding how to control their flow, you can write efficient and concise code to automate processes, process data, and solve complex problems. Remember, practice makes perfect, so don't hesitate to experiment with loops and explore their various applications in Python!

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