While-Loops.md

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In programming, loops allow you to repeat a block of code a number of times.
If there's a question like the one to the right, how many tries will it take to guess?
1 guess? 2 guesses? 4 guesses? 100 guesses?
For times when a block of code needs to run an uncertain or non-specific amount of times, you use a while loop.

Control Variables

You use a control variable to set when your loop does and doesn't run. If you want your loop to repeat until a user guesses correctly, use a boolean control variable.
Make a new project.
Add:

guessed = False

Loop Conditions

The loop repeats until a condition you set is met in what is called a conditional statement. Use your loop type and the control variable here.
Set the condition of the loop to run while guessed is not true:

while not guessed:

The body of the loop is the code that will run repeatedly.
Add the following code inside your while loop:

guess = input("Pick a number")

if int(guess) == 14:
  guessed = True
  print("You win!")

The print statement will only run after the loop has ended.
Here's what your project could look like at this point:

guessed = False

while not guessed:
    guess = input("Pick a number")
    if int(guess) == 14:
        guessed = True

print("You win!")

Recap

Use while loops when a program must run an unknown amount of times. While loops are made of a loop control variable (made first), a conditional statement (the conditions that must be met for the loop to run), and a loop body (the actual code that will run).

• Update the code to handle entries with different capitalizations.
• Add code to make the guess input statement easier to understand for the user.