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Python Code Samples

Easy snippets you can copy, study, and run in the browser editor.

46 matches
Strings & text easy

How to Process Lines of Text in Python

Strip whitespace, split a multi-line string, count words per line, and print structured summaries using basic string methods and loops.

strings text-processing splitlines
Python
text = """   Python is great!
Coding is fun.
   Python skills help you grow.   """

lines = text.strip().splitlines()
line_count = len(lines)

processed = []
for line in lines:
    stripped = line.strip()
    word_count = len(stripped.split())
    processed.append({
        "original": line,
        "stripped": stripp…
13 0 Open
Lists & loops easy

Compare Two Lists in Python: Common, Only in First, Only in Second

A beginner-friendly helper that loops over two lists and returns items common to both, items only in the first list, and items only in the second list.

lists comparison loops
Python
def compare_lists(list1, list2):
    common = []
    only_in_first = []
    only_in_second = []
    
    for item in list1:
        if item in list2:
            common.append(item)
        else:
            only_in_first.append(item)
    
    for item in list2:
        if item not in list1:
            only_in_second…
14 0 Open
Lists & loops easy

Enumerate a Python List with a Custom Start Index

Iterate over a list with an index that starts at a custom value (like 5) using Python's built-in enumerate() function with the start parameter.

enumerate iteration loops
Python
fruits = ["apple", "banana", "cherry", "date"]

for index, fruit in enumerate(fruits, start=5):
    print(f"{index}: {fruit}")
15 0 Open
Lists & loops easy

Extract Data by Type from a List in Python: Numbers and Strings

Loop through a mixed list to filter out numeric and string values into separate lists.

lists filtering type-checking
Python
def extract_numbers(items):
    """Extract all numeric values from a mixed list."""
    numbers = []
    for item in items:
        if isinstance(item, (int, float)) and not isinstance(item, bool):
            numbers.append(item)
    return numbers


def extract_strings(items):
    """Extract all string values from a…
14 0 Open
Lists & loops easy

Find All Occurrences of an Item in a Python List

Loop through a list with enumerate() to collect the index of every match for a target value.

list enumerate loops
Python
def find_all(data, target):
    """Return indices of every occurrence of target in a list."""
    indices = []
    for index, item in enumerate(data):
        if item == target:
            indices.append(index)
    return indices


if __name__ == "__main__":
    sample = [10, 20, 30, 20, 40, 20, 50]
    target_value …
14 0 Open
Lists & loops easy

Format Lists of Tuples into Numbered Lines in Python

This code loops through a list of (name, grade) tuples and formats each into a numbered line using enumerate and f-strings.

enumerate formatting lists
Python
def format_students(students):
    formatted = []
    for i, student in enumerate(students, start=1):
        name, grade = student
        formatted.append(f"{i}. {name}: {grade}")
    return "\n".join(formatted)


if __name__ == "__main__":
    students = [
        ("Alice", 92),
        ("Bob", 85),
        ("Charl…
15 0 Open
Lists & loops easy

Generate Data Helper for Beginners in Python

Define two functions that create a random list of integers and then compute basic summary statistics like count, total, average, maximum, and minimum using simple loops.

random loops lists
Python
from random import randint

def build_dataset(size: int, max_val: int) -> list[int]:
    data = []
    for _ in range(size):
        data.append(randint(1, max_val))
    return data

def summarize(data: list[int]) -> dict[str, float]:
    total = 0
    maximum = data[0]
    minimum = data[0]
    for value in data:
   …
12 0 Open
Lists & loops easy

How to Build a Text Processor with Lists and Loops in Python

A beginner-friendly Python script that analyzes text by counting sentences, words, and word lengths using lists and for loops, then prints the results.

text-processing loops lists
Python
def process_text(text):
    """Simple text processor for beginners using lists and loops."""
    sentences = text.replace('!', '.').replace('?', '.').split('.')
    words = text.split()
    
    word_counts = []
    for sentence in sentences:
        sentence_word_count = len(sentence.split())
        word_counts.appe…
12 0 Open
Lists & loops easy

How to Calculate a Cumulative Sum in Python

Build a new list where each element equals the running total of all numbers up to that index in the original list.

lists cumulative-sum loops
Python
numbers = [1, 2, 3, 4, 5]
cumulative_sum = []
running_total = 0

for num in numbers:
    running_total += num
    cumulative_sum.append(running_total)

print(cumulative_sum)
12 0 Open
Lists & loops easy

How to Convert Data Types in Python Lists

Convert a mixed list of values to integers, floats, or strings based on their content, with graceful fallback for unparseable strings.

type-conversion loops lists
Python
def convert_data(data):
    """Convert a mixed list of values to strings, ints, and floats."""
    result = []
    for item in data:
        if isinstance(item, (int, float)):
            result.append(str(item))
        elif isinstance(item, str):
            try:
                if '.' in item:
                    r…
13 0 Open
Lists & loops easy

How to Count Occurrences of a Value in a Python List

Counts how many times a specific value appears in a list using a simple loop and a counter variable.

counting loops lists
Python
def count_occurrences(data, target):
    count = 0
    for item in data:
        if item == target:
            count += 1
    return count


if __name__ == "__main__":
    numbers = [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]
    target_value = 5
    result = count_occurrences(numbers, target_value)
    print(f"The value {targ…
13 0 Open
Lists & loops easy

How to Count, Double, and Find Max in a Python List

Three beginner-friendly Python functions that count even numbers, double each value, and find the maximum in a list using simple loops.

lists loops beginner
Python
def count_even_numbers(numbers):
    """Return the count of even numbers in a list."""
    count = 0
    for num in numbers:
        if num % 2 == 0:
            count += 1
    return count


def double_values(numbers):
    """Return a new list with each value doubled."""
    doubled = []
    for num in numbers:
     …
14 0 Open
Lists & loops easy

How to Filter Even Numbers and Square Them in Python

Create two beginner-friendly helper functions that filter even numbers and compute squares of a number list using loops, then print the results along with the sum and average.

loops filtering math
Python
def get_even_numbers(numbers):
    evens = []
    for num in numbers:
        if num % 2 == 0:
            evens.append(num)
    return evens

def get_squares(numbers):
    squares = []
    for num in numbers:
        squares.append(num ** 2)
    return squares

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

even_numbers …
15 0 Open
Lists & loops easy

How to Find Local Maxima in a Python List

Return the indices of all local maxima in a numeric list, where a peak is an element greater than both its immediate neighbors.

local-maxima peaks list
Python
def find_peaks(numbers):
    """
    Return the indices of local maxima in a numeric list.
    A local maximum is an element greater than both its neighbors.
    """
    if len(numbers) < 3:
        return []
    
    peaks = []
    for i in range(1, len(numbers) - 1):
        if numbers[i] > numbers[i - 1] and number…
15 0 Open
Lists & loops easy

How to Loop Through Lists in Python for Beginners

Transform, filter, sum, and find the maximum in a Python list using basic for loops and conditionals.

lists loops iteration
Python
def transform_data(numbers):
    """Basic transformation examples using lists and loops."""
    doubled = []
    for n in numbers:
        doubled.append(n * 2)
    return doubled


def filter_even(numbers):
    """Keep only even numbers using a loop and condition."""
    evens = []
    for n in numbers:
        if n …
14 0 Open
Lists & loops easy

How to Merge Two Lists in Python

Merge two Python lists into a single combined list by appending each element with a simple loop, achieving the same result as the + operator.

lists merge loops
Python
def merge_lists(list_a, list_b):
    merged = []
    for item in list_a:
        merged.append(item)
    for item in list_b:
        merged.append(item)
    return merged


if __name__ == "__main__":
    fruits = ["apple", "banana"]
    vegetables = ["carrot", "spinach"]
    result = merge_lists(fruits, vegetables)
  …
14 0 Open
Lists & loops easy

How to Normalize a List of Numbers in Python

This Python function normalizes a list of numeric values to the range [0, 1] using min-max scaling, returning a new list and leaving the original unchanged.

lists loops normalization
Python
def normalize(data):
    """
    Normalize a list of numeric values to the range [0, 1].
    Returns a new list, leaving the original unchanged.
    """
    if not data:
        return []
    
    min_val = min(data)
    max_val = max(data)
    
    # Handle the edge case where all values are identical
    if min_val …
17 0 Open
Lists & loops easy

How to Parse Bullet Points in Python

Extract bullet point items from raw text by splitting lines and filtering those that start with '- ' or '* '.

text parsing bullet points loops
Python
def parse_bullet_points(text):
    """Extract bullet point items from raw text."""
    lines = text.splitlines()
    items = []
    
    for line in lines:
        stripped = line.strip()
        if stripped.startswith("- ") or stripped.startswith("* "):
            item = stripped[2:]
            if item:
           …
13 0 Open
Lists & loops easy

How to Parse Delimited Data into a Python List

Splits a pipe-delimited string, strips whitespace, filters empty items, and returns a clean list with a loop.

strings lists loops
Python
def parse_data(raw_data):
    """Parse a pipe-delimited string into a list of cleaned items."""
    items = raw_data.split("|")
    parsed = []
    for item in items:
        cleaned = item.strip()
        if cleaned:
            parsed.append(cleaned)
    return parsed


if __name__ == "__main__":
    data = "  apple…
15 0 Open
Lists & loops easy

How to Process Text Lines with Lists and Loops in Python

This code processes a list of text lines by stripping whitespace, converting to uppercase, and reporting character counts per line and totals.

lists loops text-processing
Python
def process_text(lines):
    """Convert a list of text lines to uppercase and report line statistics."""
    processed = []
    total_chars = 0
    
    for index, line in enumerate(lines, start=1):
        cleaned = line.strip().upper()
        processed.append(cleaned)
        total_chars += len(cleaned)
        pri…
12 0 Open
Lists & loops easy

How to Process Text into Words in Python

Splits a string into words, strips punctuation, and returns a list of uppercase words using a loop.

text-processing loops strings
Python
def convert_text_processor(text):
    words = text.split()
    processed = []
    
    for word in words:
        clean = word.strip('.,!?;:')
        if len(clean) > 0:
            processed.append(clean.upper())
    
    return processed

if __name__ == "__main__":
    sample_text = "Hello, world! This is a Python e…
12 0 Open
Lists & loops easy

How to Process Text with Lists and Loops in Python

A beginner-friendly text processor that splits a sentence into words, filters by length, counts vowels, and reports results using lists and loops.

lists loops strings
Python
text = "Python makes text processing easy and fun"

words = text.lower().split()

print("Words in the sentence:")
for index, word in enumerate(words, start=1):
    print(f"{index}. {word}")

filtered_words = [word for word in words if len(word) > 3]

print(f"\nWords longer than 3 characters: {filtered_words}")

letter…
14 0 Open
Lists & loops easy

How to Process Text with Lists and Loops in Python

Iterate over a list of text lines to count words, show uppercase versions, and report character counts per line.

lists loops enumerate
Python
# text_processor.py

def process_text(lines):
    """Count words, show uppercase, and count characters per line."""
    total_words = 0
    print("Line-by-line analysis:")
    for i, line in enumerate(lines, start=1):
        words = line.split()
        total_words += len(words)
        print(f"  Line {i}: {len(words…
17 0 Open
Lists & loops easy

How to Reverse a List in Place Without Using reverse() in Python

A two-pointer while loop swaps elements from both ends toward the center to reverse a list in place without creating a copy.

lists in-place two-pointer
Python
def reverse_list_in_place(lst):
    left = 0
    right = len(lst) - 1
    while left < right:
        lst[left], lst[right] = lst[right], lst[left]
        left += 1
        right -= 1


if __name__ == "__main__":
    my_list = [1, 2, 3, 4, 5]
    print("Original:", my_list)
    reverse_list_in_place(my_list)
    prin…
14 0 Open

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