Output of Python Program | Set 8 (Exception Handling)

Output of Python Program | Set 8 (Exception Handling)

Exception handling is a crucial aspect of writing robust Python programs. It allows you to manage errors gracefully without crashing your program. In this blog, we'll explore various examples demonstrating how Python handles exceptions and what outputs you can expect from these programs.

Basic Try-Except Block

The simplest form of exception handling uses a try-except block to catch and handle exceptions:

try:
    result = 10 / 0
except ZeroDivisionError:
    print("Cannot divide by zero")

Output:

Cannot divide by zero

Here, attempting to divide by zero raises a ZeroDivisionError, which is caught and handled by printing a message.

Catching Multiple Exceptions

You can catch multiple exceptions in a single except block by using a tuple:

try:
    num = int("abc")
except (ValueError, TypeError):
    print("Caught a ValueError or TypeError")

Output:

Caught a ValueError or TypeError

Using Else and Finally

The else block executes if no exception occurs, while finally runs regardless of exceptions:

try:
    num = int("123")
except ValueError:
    print("Conversion failed")
else:
    print("Conversion succeeded:", num)
finally:
    print("This will always execute")

Output:

Conversion succeeded: 123
This will always execute

Raising Exceptions

You can also manually raise exceptions using the raise keyword:

def check_age(age):
    if age < 18:
        raise ValueError("Age must be at least 18")
    else:
        print("Age is valid")

try:
    check_age(15)
except ValueError as e:
    print(e)

Output:

Age must be at least 18

Practice Problem

Write a Python program that asks the user to input a number and divides 100 by that number. Use exception handling to catch any errors like division by zero or invalid input, and print appropriate error messages.

# Practice Problem:
# Input a number from user and divide 100 by it
# Handle exceptions for invalid input and division by zero

try:
    # Your code here
    pass
except Exception as e:
    print("Error:", e)

Solution to Practice Problem

try:
    num = int(input("Enter a number to divide 100 by: "))
    result = 100 / num
except ValueError:
    print("Invalid input! Please enter an integer.")
except ZeroDivisionError:
    print("Cannot divide by zero.")
else:
    print("Result is:", result)

This program prompts for user input, handles invalid inputs and division by zero gracefully, and outputs the result if no errors occur.

Summary

Exception handling helps make your Python programs more reliable by managing runtime errors. Using try-except blocks, you can catch exceptions, clean up with finally, and raise your own errors when necessary. Practice writing and handling exceptions to write better, more fault-tolerant code.