Python Programs
Python Programs - Home
Introduction to Python
Print "Hello, World!"
Print your name, age, and country
Print the result of a simple arithmetic expression
Use sep and end in print()
Print a poem or song lyrics
Print a multi-line quote using triple quotes
Display ASCII art using print()
Format and print full name using + and ,
Print today's date using formatted output
Display types of several variables with type()
Print truth values of Boolean expressions
Print Python keywords using the keyword module
Variables and Data Types
Assign values to different types (int, float, str, bool)
Perform all arithmetic operations on two numbers
Swap two variables using a temporary variable
Swap variables without using a third variable
Convert string to int and float
Convert float to int and round to N decimal places
Evaluate a complex expression using variables
Get the memory size of a variable using sys.getsizeof()
Demonstrate dynamic typing in Python
Accept string input and display its ASCII values
Display the binary, octal, and hex of a number
Use isinstance() to check variable type
Show precision differences between float and Decimal
Display formatted currency and percentage
Display a boolean expression result with explanation
Input and Output
Take user input and print greeting
Input two numbers and print their sum
Input radius and print area and circumference of a circle
Input name and marks of a student, print formatted result
Take input in one line and split into variables
Read multiple lines of input and print each line reversed
Print formatted date using f-strings
Format and align strings using format()
Display table of values using tabular format
Input three numbers and display average
Input a character and print its ASCII code
Accept time input and display it in 12/24 hour format
Read a password and hide it using getpass
Format large numbers using underscores and separators
Operators and Expressions
Calculate the perimeter and area of a rectangle
Compute compound interest
Check if a number is even or odd using modulo
Check if a number is divisible by 3 and 5
Use relational operators between two inputs
Use logical and, or, not to combine conditions
Perform bitwise AND, OR, XOR on two numbers
Evaluate an expression using parentheses and priorities
Use augmented assignment (+=, *=, etc.) operators
Calculate the average of a list of numbers
Find the power of a number using ** and pow()
Implement a basic BMI calculator
Convert minutes to hours and minutes
Check whether a number is in a given range
Calculate speed = distance/time and convert units
Module 2: Control Structures
Conditional Statements
Check if a number is positive, negative, or zero
Find the largest of three numbers
Check whether a number is even or odd
Check if a year is a leap year
Determine grade based on marks
Check if a character is a vowel or consonant
Find if a number is divisible by both 3 and 5
Validate user login credentials (hardcoded username/password)
Check if a person is eligible to vote
Compare three strings and print the longest
Check if a number is a multiple of another
Determine if a triangle is scalene, isosceles, or equilateral
Check if a number lies within a given range
Convert temperature from Celsius to Fahrenheit and categorize (hot/cold)
Simple interest or compound interest calculator with user choice
Determine electricity bill category based on units consumed
Find roots of a quadratic equation (real/imaginary)
Check if a character is uppercase, lowercase, digit, or special character
Find the absolute value of a number
Check if a string starts with a specific letter
Looping Statements
Print numbers from 1 to 100
Print even numbers between 1 to 50
Print multiplication table of a given number
Calculate factorial using a while loop
Calculate the sum of digits of a number
Count digits, alphabets, and special characters in a string
Find the sum of first n natural numbers
Reverse a number using loop
Check if a number is prime
Generate Fibonacci series up to n terms
Print all prime numbers in a given range
Display a pattern (e.g., pyramid, triangle using *)
Find the Least Common Multiple (LCM) of two numbers
Display numbers divisible by 7 but not by 5
Calculate the power of a number using a loop
Count how many times a digit occurs in a number
Sum of even and odd numbers in a list
Create a menu-driven program with loop and conditions
Print ASCII values of all characters from A to Z
Check if a number is an Armstrong number
Module 3: Functions and Recursion
Defining and Using Functions
Function to add two numbers
Function to check if number is even or odd
Function to return the factorial of a number
Function to convert Celsius to Fahrenheit
Function to calculate the square and cube of a number
Function to calculate the area of a circle
Function to find the maximum of three numbers
Function to check if a string is a palindrome
Function to calculate BMI and categorize
Function to reverse a string
Function to compute compound interest
Function to return number of vowels in a string
Function to find sum and average of a list
Function to count the number of uppercase and lowercase letters
Function to sort a list without using sort()
Function to find GCD using Euclidean method
Function to return nCr (combinations)
Function with default arguments (e.g., greeting message)
Function to generate a list of prime numbers in a range
Function to check if a number is perfect or not
Recursion Basics
Recursive function for factorial
Recursive function for Fibonacci
Recursive function to compute GCD
Recursive function to compute sum of first N numbers
Recursive function to reverse a string
Recursive function to calculate power of a number
Recursive function to find max element in a list
Recursive function to convert decimal to binary
Recursive function to print elements of a list
Recursive function to find length of a string
Recursive function to find LCM
Recursive function to flatten a nested list
Recursive function to calculate sum of digits
Recursive palindrome check
Recursive function to print numbers from N to 1
Recursive function to check if a list is sorted
Recursive function for binary search
Recursive function to find all permutations of a string
Recursive function to check if a number is prime
Recursive function to count total vowels in a sentence
Recursive function to count the frequency of characters in a string
Module 4: Strings and Collections
String Manipulation
Count vowels and consonants in a string
Check if a string is a palindrome
Convert all characters in a string to uppercase
Find the frequency of each character
Replace spaces with hyphens
Remove all punctuation from a string
Count the number of words in a sentence
Find the longest word in a sentence
Swap case of all characters in a string
Check if two strings are anagrams
Remove duplicate characters from a string
Find common characters between two strings
Reverse a string using slicing and loop
Capitalize the first letter of each word
Find substring occurrences in a string
Remove leading and trailing spaces
Extract numbers from a string
Split a string and join using hyphen
Sort characters in a string alphabetically
Find ASCII value of each character
Lists and Tuples
Create a list of N numbers from user input
Find sum and average of list elements
Count occurrences of an element
Find the maximum and minimum in a list
Sort a list without using built-in functions
Remove duplicates from a list
Add and remove elements from a list
Reverse a list using slicing and loop
Merge two lists
Find the second largest number in a list
Check if a list is sorted
List comprehension: squares of even numbers
Create a nested list and access elements
Create and unpack a tuple
Convert list to tuple and vice versa
Find common elements in two lists
Find the intersection and difference of two lists
Delete all occurrences of an element from a list
Find the most frequent element in a list
Rotate elements of a list to the right by k positions
Dictionaries and Sets
Create a dictionary of student names and marks
Count frequency of words in a sentence
Merge two dictionaries
Add, update, and delete a key-value pair
Iterate over dictionary keys and values
Find the key with the highest value
Sort a dictionary by values
Invert a dictionary (swap keys and values)
Check if a key exists in dictionary
Convert two lists into a dictionary
Remove duplicates from a list using set
Find union, intersection, difference of two sets
Check if one set is a subset of another
Add and remove elements from a set
Count number of unique words in a sentence
Create a set of vowels from a string
Find common characters using set intersection
Create dictionary from a string with character counts
Dictionary comprehension to map numbers to their squares
Find symmetric difference between two sets
Module 5: Object-Oriented Programming (OOP)
Lesson 1: Classes and Objects
Create a Person class and print name and age
Create a Rectangle class with area and perimeter methods
Define a Book class and display book details
Create a Car class with attributes and a display method
Define a BankAccount class with deposit and withdrawal
Create a Circle class to compute area and circumference
Create a Student class with method to calculate grade
Define a Product class with method to apply discount
Create an Employee class and print full profile
Define a class to convert Celsius to Fahrenheit
Add a method to update an attribute after initialization
Add class variables and track instance count
Create a Laptop class with warranty checker method
Demonstrate instance, class, and static methods
Create a class to store and display contact details
Define a Movie class to show ratings and reviews
Create a class with list attributes and methods to append
Design a Triangle class and check for valid triangle
Define a Clock class to show current time
Create a class to manage inventory items
Constructors and Methods
Use __init__ to initialize student details
Constructor with default parameters
Create a class to manage bank accounts with init balance
Define methods to increment and decrement a counter
Create a Timer class with start/stop functionality
Define a Point class and calculate distance from origin
Constructor to create list of items, method to sort them
Add a method to validate data inside a class
Define a class Laptop with a discount method
Create a class Course to register and drop students
Initialize employee details and method to promote
Define a class with method to check palindrome names
Constructor chaining using default values
Define an Invoice class with total price calculator
Class with init method validating input type (int/str)
Use method to return string representation of object
Constructor initializing user login credentials
Constructor-based multiplication table printer
Define a class with password validator
Constructor that reads user input at object creation
Inheritance and Polymorphism
Create a base class Animal and subclass Dog
Use super() to call parent class constructor
Define a Shape class and subclass Rectangle, Circle
Override a method in child class
Demonstrate multi-level inheritance
Create a Person base class and Teacher, Student subclasses
Implement multiple inheritance (e.g., Artist, Engineer)
Create a base class Vehicle with subclasses Car, Bike
Demonstrate method overriding and polymorphism
Base class Account with methods deposit(), withdraw()
Use isinstance() to check object type
Polymorphic function that works with different data types
Create abstract base class with abc module
Demonstrate duck typing with walk() method
Create a Media class with play() method overridden
Inherit constructor and add extra attributes in child
Use hasattr() and getattr() to access object info
Demonstrate inheritance with __str__() method
Extend parent class with new method in child class
Base class Polygon with triangle, square subclasses
Module 6: File and Exception Handling
Reading/Writing Files
Write a string to a text file
Read and print contents of a text file
Append text to an existing file
Count number of lines in a file
Count number of words and characters in a file
Copy contents from one file to another
Merge contents of two files into a third file
Write a list of strings to a file (one per line)
Read file and print lines with line numbers
Remove all blank lines from a file
Write user-entered data repeatedly into a file until "exit"
Find and replace a word in a file
Check if a file exists before reading (using os.path.exists())
Read a large file line-by-line (memory-efficient)
Read a file and extract only numeric data
Write and read Unicode characters
Create a file from scratch with student records
Sort lines of a text file alphabetically
Write reversed lines of a file to another file
Save execution logs with timestamps into a log file
CSV and JSON Files
Read a CSV file and print each row
Write a list of dictionaries to a CSV file
Append a row to an existing CSV
Read a CSV with headers using DictReader
Filter rows from a CSV file (e.g., students > 80 marks)
Convert CSV file to JSON format
Write Python dictionary to a JSON file
Read JSON file and access nested data
Validate JSON using json.loads()
Convert JSON to dictionary and loop through data
Extract all values of a specific key from JSON
Read a list of dictionaries from JSON and print in table
Store user preferences/settings in a JSON file
Append data to an existing JSON array
Pretty-print JSON with indentation
Read CSV and calculate statistics (mean, median)
Write dictionary with non-ASCII characters to JSON
Convert list of tuples into JSON array
Update values in a loaded JSON object and save
Build a JSON file containing user data entered via input
Try-Except Blocks
Handle division by zero
Catch invalid input and convert it to integer
Handle file not found error
Multiple exception handling (ValueError, ZeroDivisionError)
Use else and finally with try block
Catch and print stack trace using traceback
Nested try-except blocks
Custom exception: raise error if age < 18
Handle type errors in addition of incompatible types
Validate file extension before opening file
Use assertions to check preconditions
Exception handling in list indexing
Exception handling while opening URL (mocked)
Raise exception if string is not alphabetic
Try-except-finally to manage database connection (mock)
Raise exception for password too short
Log exception details to a file
Retry block until valid integer input is entered
Handle key errors in dictionary access
Handle invalid JSON format using try-except
Module 7: Advanced Python Features
Lambda, Map, Filter, Reduce
Use lambda to square a number
Use lambda to check if a number is even
Sort a list of tuples by the second item using lambda
Map: convert list of strings to uppercase
Map: square each number in a list
Filter: extract only odd numbers from a list
Filter: select strings longer than 5 characters
Reduce: calculate the sum of a list
Reduce: find the maximum in a list
Apply map and filter together (e.g., square only even numbers)
Use lambda to create a mini calculator
Map: convert temperatures from Celsius to Fahrenheit
Filter: extract palindromes from a list
Use reduce() to calculate factorial
Use lambda to return the length of each string in a list
Combine map() and zip() for parallel processing
Use lambda inside sorted() for custom sort
Remove all negative numbers from a list using filter
Multiply all elements using reduce()
Map: convert list of names to title case
Comprehensions
List of squares from 1 to 10 using list comprehension
Create a list of even numbers between 1–50
Create a list of strings with length > 5
Create a dictionary of numbers and their cubes
Create a set of first letters of all words in a list
Reverse each string in a list using comprehension
Convert all vowels in a string to uppercase using list comprehension
Dictionary: word lengths from a sentence
Matrix transpose using nested list comprehension
Filter out None values from a list
Flatten a 2D list using list comprehension
Get only unique vowels from a string
Dictionary: count occurrences of characters
Remove whitespace from each string in a list
Convert a list of Fahrenheit to Celsius
Filter only prime numbers from a range
List comprehension to remove punctuation from string
Convert a list of tuples into a dictionary
Create a list of perfect squares less than 100
Convert string of digits into a list of integers
Decorators and Generators
Create a basic decorator to log function call
Decorator to measure execution time
Decorator to check user authentication
Decorator to convert output to uppercase
Chained decorators: log and format return value
Generator: yield numbers from 1 to N
Generator to yield even numbers up to N
Generator to yield Fibonacci sequence
Generator to read large file line by line
Use generator expression to sum squares of numbers
Decorator to validate function input (e.g., age > 0)
Create a generator for infinite odd numbers
Decorator to retry a function N times on failure
Generator to yield prime numbers under 100
Decorator to catch and log exceptions
Generator to yield all substrings of a string
Create a decorator that adds a greeting to function output
Generator to simulate countdown
Decorator that prevents function from executing twice
Use next() to manually iterate through a generator
Module 8: Data Structures
Manual Implementation - Stack (LIFO) and Queue (FIFO)
Stack (LIFO)
Implement queue using list (enqueue, dequeue)
Implement circular queue using list
Simulate a ticket booking queue system
Priority queue implementation using list of tuples
Implement queue using two stacks
Implement deque (double-ended queue)
Simulate printer queue with priorities
Implement queue using a linked list
Patient registration system using queue
Circular buffer simulation
Queue (FIFO)
Implement queue using list (enqueue, dequeue)
Implement circular queue using list
Simulate a ticket booking queue system
Priority queue implementation using list of tuples
Implement queue using two stacks
Implement deque (double-ended queue)
Simulate printer queue with priorities
Implement queue using a linked list
Patient registration system using queue
Circular buffer simulation
Built-in Structures (from collections and heapq)
Use deque for append and pop from both ends
Implement stack and queue using deque
Palindrome checker using deque
Use Counter to count frequency of words in a paragraph
Use defaultdict to categorize list of tuples by key
Group words by their starting letter using defaultdict
Use OrderedDict to remember order of insertions
Use heapq to implement a min-heap
Use heapq to get top N smallest/largest elements
Create a priority queue with heapq and tuples
Convert list into heap and perform heapify
Merge multiple sorted lists using heap
Use Counter to find the most common element
Use deque to rotate a list
Use namedtuple to create structured records
Compare dict vs OrderedDict for insertion order
Implement leaderboard with top scores using heapq
Use ChainMap to merge multiple dictionaries
Use Counter to compare frequency of characters
Create a min-heap for task scheduling
Module 9: Data Science with Python (Intro)
NumPy Basics
Create a 1D, 2D, and 3D NumPy array
Create arrays with zeros(), ones(), arange(), and linspace()
Reshape a 1D array into a 2D array
Perform element-wise arithmetic operations
Slice and index a NumPy array
Find mean, median, standard deviation, and variance
Matrix multiplication and dot product
Transpose a matrix
Create identity and diagonal matrices
Stack arrays vertically and horizontally
Filter elements using boolean indexing
Replace negative numbers with 0 in an array
Flatten a multi-dimensional array
Use broadcasting to add scalar to array
Find max and min value in a NumPy array
Sort rows and columns of a 2D array
Generate a random matrix
Check memory usage of array vs Python list
Create a histogram of random normal data
Solve linear equations using NumPy
Pandas for DataFrames
Create a DataFrame from a dictionary
Read a CSV file into a DataFrame
Display column names and basic statistics (.describe())
Access rows and columns using loc and iloc
Filter rows based on condition
Add and drop columns in a DataFrame
Group data by a column and calculate average
Handle missing values (fill, drop, interpolate)
Sort DataFrame by a column
Rename columns and indexes
Merge two DataFrames (inner, outer joins)
Apply a function to a column
Convert a column to datetime
Create a new column from existing ones
Export DataFrame to CSV and Excel
Plot bar chart from column values
Filter rows where string column contains a keyword
Load and analyze Excel files using read_excel()
Concatenate multiple DataFrames
Pivot and unpivot tables using pivot_table() and melt()
Matplotlib and Seaborn
Plot a simple line chart with labels
Plot bar chart of student scores
Plot pie chart of product sales
Create a histogram of ages
Plot multiple lines on one graph
Customize chart titles, axis labels, grid
Plot scatter plot of two variables
Create subplots in one figure
Read data from CSV and plot graph
Save a plot to a file (PNG, JPG)
Create boxplot to compare distributions
Create heatmap using Seaborn
Plot pairplot of numeric features
Show correlation matrix using heatmap
Plot distribution plot of scores using Seaborn
Customize colors and styles of plots
Plot bar chart with error bars
Add annotations and labels to data points
Compare multiple categories using grouped bar chart
Visualize time series data using line plots
Module 10: Working with APIs and Web
requests and APIs
Make a GET request to a public API (e.g., JSONPlaceholder)
Print the status code and headers of a response
Parse and display JSON from an API response
Make a POST request with JSON payload
Send parameters with a GET request using params
Download an image or file from a URL
Get current weather data using OpenWeatherMap API
Fetch a random joke or quote from an API
Validate and format API response using json module
Handle 404 or failed API requests with try-except
Create a reusable function to call any API endpoint
Access GitHub user data using GitHub REST API
Send data to a mock server (e.g., reqres.in) using POST
Parse nested JSON and display it in tabular form
Build a function that returns COVID stats for a country
Automate currency conversion using a Forex API
Display top headlines using NewsAPI
Monitor a website’s uptime using repeated API pings
Extract NASA Astronomy Picture of the Day using their API
Store API responses in a JSON file locally
Web Scraping with BeautifulSoup
Scrape the title of a web page
Extract all hyperlinks from a page
Scrape all
to
tags from a site
Extract text from all
tags
Get article titles from a news site homepage
Scrape job listings from a job portal
Scrape product names and prices from an e-commerce site
Extract table data from a webpage (e.g., Wikipedia)
Scrape weather forecast from a local site
Download all images from a webpage
Scrape blog post titles and URLs
Extract all email addresses from a website
Use CSS selectors to target specific elements
Handle pagination in scraping (next page button)
Store scraped data in CSV format
Store scraped data in a JSON file
Build a mini command-line scraper for quotes
Filter scraped elements using tag attributes
Detect and skip broken URLs
Integrate requests + BeautifulSoup in a scraper pipeline
JSON Handling
Convert a Python dictionary to JSON string
Convert JSON string to dictionary
Write dictionary data to a JSON file
Read JSON file and access nested values
Pretty-print JSON with indentation
Load JSON from a web API and parse it
Handle invalid JSON with try-except
Update a value inside a loaded JSON object
Delete a key from a JSON object and save
Add new key-value pairs to an existing JSON file
Merge two JSON objects into one
Convert a JSON array to a list of Python objects
Search for a value in nested JSON
Save a list of students' data into a JSON file
Load and loop through JSON to print formatted output
Convert a list of objects to JSON with custom encoder
Serialize a class instance to JSON
Deserialize JSON string into custom Python class
Validate a JSON structure manually (e.g., required fields)
Compare two JSON objects and highlight differences
Module 11: GUI and Automation
GUI Programming with Tkinter
Create a basic GUI window with title and size
Add a label and button to a window
Display user-entered text using an input field
Build a simple calculator (add, subtract, multiply, divide)
Create a login form with username and password fields
Build a temperature converter (Celsius ↔ Fahrenheit)
Create a dropdown menu and display selected value
Add radio buttons for selecting gender
Add checkboxes and show selected hobbies
Use frames and grids to organize widgets
Display list of items and select from it
File browser: open and read a text file
Create a to-do list application with add/remove
Create a feedback form with validation
Add progress bar and simulate loading
Create GUI to browse and display images
Change theme/colors dynamically
Add menu bar with File/Edit/Help options
Connect GUI with SQLite to store user data
Show popup message boxes (info, error, warning)
Automation with os, shutil, datetime, and schedule
List all files and folders in a directory
Create, rename, and delete files/folders using os
Automatically rename multiple files with a pattern
Copy/move/delete files using shutil
Backup a folder to another location
Get file creation/modification date
Convert filenames to lowercase in a directory
Create a daily log file with timestamp
Schedule a task to run every 5 minutes using schedule
Delete all .tmp files from a folder
Check disk usage of a folder
Record current time and write it into a file every 10 sec
Take automatic screenshot every 30 seconds
Send a reminder every hour using notification
Create a zip backup of a folder
Script to clean up downloads folder
Automatically email a log file at midnight
Archive files older than 7 days
Generate time-based filenames for saving reports
Automate system shutdown after a timer
Automating Web Tasks with pyautogui and selenium
Automate keyboard typing using pyautogui
Automate mouse clicks and cursor movements
Take automatic screenshots every N seconds
Open a website and search using selenium
Log in to a website automatically using credentials
Scrape product prices from an e-commerce site
Fill and submit a Google form using Selenium
Download files from a website
Send automated WhatsApp message via web
Open and control YouTube (play, pause using hotkeys)
Automate a web-based calculator
Click a button by its text or CSS class
Scroll down a webpage using Selenium
Capture alert popups and handle them
Automate form filling on a job portal
Use headless browser for faster automation
Wait for page to load before scraping content
Screenshot a webpage and save
Fill a captcha and stop at verification
Build a bot to auto-like latest tweets/posts
Module 12: Mini Projects
Beginner Level Projects
To-Do List App (Console)
Quiz Game
Number Guessing Game
Simple ATM Simulator
Contact Book
Calculator with GUI (Tkinter)
Digital Clock (GUI)
Dice Roller Simulator
Password Generator
Simple Alarm Clock
Intermediate Projects
Student Marks Report Generator
Weather App using API
Currency Converter (with API or static rates)
Flashcard App for Learning
Text File Analyzer
Typing Speed Tester
BMI Calculator with GUI
Age Calculator
Unit Converter (length, weight, temperature)
Library Book Management (console or GUI)
Module 13: Capstone Projects
Capstone Projects (Intermediate to Advanced)
Student Result Management System
E-Library Management System
Expense Tracker App
Weather Dashboard (API + GUI)
Online Quiz Application with Scoreboard
Portfolio Website Generator (CLI/GUI)
Job Search Automation Bot
Inventory and Billing System for a Store
Python Chatbot (GUI or Terminal)
Movie Recommendation App (Content-Based)
School Attendance System with CSV and Visualization
Budget Planner (Pie Charts + Reports)
File Organizer Utility (Drag-and-Drop GUI)
Daily Journal App
Task Manager App with Notifications
Currency + Crypto Converter App
PDF Tools Suite
Mini Social Media Feed
Resume Parser and Keyword Matcher
Data Dashboard using Pandas + Matplotlib + Tkinter
Automating Web Tasks with pyautogui and selenium

Python Programs

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Convert string to int and float - Python Program

In Python, strings can be converted to integers using the int() function and to floating-point numbers using the float() function.

Converting a string to an integer:

The int() function is used to convert a string representing a whole number into an integer.

Converting a string to a float:

The float() function is used to convert a string representing a decimal number into a floating-point number.

Python


str_val = "123"
int_val = int(str_val)
float_val = float(str_val)

print(int_val)
print(float_val)

Output

 
OUTPUT  :
123
123.0

to

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Python Programs

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Convert string to int and float - Python Program

Output