Python While Loop Examples: Looping Until a Condition is Met

📚 Quick Study Guide

• 🔄 Definition: A `while` loop in Python repeatedly executes a block of code as long as a condition is true.
• 🔑 Syntax: python while condition: # code to be executed
• ⚠️ Condition: The condition is evaluated before each execution of the loop body. If the condition is false at the start, the loop body is never executed.
• ♾️ Infinite Loops: If the condition is always true, the loop will run forever. Ensure your condition eventually becomes false.
• 📈 Increment/Decrement: Inside the loop, you often need to modify variables used in the condition to ensure the loop terminates.
• 🧱 Break Statement: The `break` statement can be used to exit a `while` loop prematurely, regardless of the condition.
• 🤸 Continue Statement: The `continue` statement skips the rest of the current iteration and proceeds to the next iteration of the loop.

Practice Quiz

1. What is the primary purpose of a `while` loop in Python?
   1. To define a function
   2. To repeat a block of code until a condition is met
   3. To create a class
   4. To handle exceptions
2. What happens if the condition in a `while` loop is always true?
   1. The loop will not execute.
   2. The program will crash.
   3. The loop will execute once.
   4. The loop will run indefinitely (infinite loop).
3. Which statement is used to immediately exit a `while` loop, regardless of the condition?
   1. `continue`
   2. `pass`
   3. `break`
   4. `exit`
4. What does the `continue` statement do in a `while` loop?
   1. Exits the loop entirely.
   2. Skips the current iteration and proceeds to the next.
   3. Restarts the loop from the beginning.
   4. Prints a message to the console.
5. What will be the output of the following code? python i = 1 while i < 5: print(i) i += 1
   1. 1 2 3 4 5
   2. 1 2 3 4
   3. 0 1 2 3 4
   4. Error
6. What will be the output of the following code? python i = 0 while i < 5: i += 1 if i == 3: continue print(i)
   1. 1 2 3 4 5
   2. 1 2 4 5
   3. 1 2
   4. Error
7. What is a potential issue with using `while` loops?
   1. They are faster than `for` loops.
   2. They can lead to infinite loops if not used carefully.
   3. They can only iterate through numbers.
   4. They cannot be used with conditional statements.