In Python, the body of the while loop is determined through indentation. Now you know how while loops work, so let's dive into the code and see how you can write a while loop in Python. How to use "For Loop" In Python, "for loops" are called iterators. A loop that uses a sentinel value is called a sentinel-controlled loop. While Loop. Python while Loop: In the previous article, we have briefly discussed the for Loop in Python.. Now, it’s time to move to the next and last type of Loop statement which is while Loop. Loops iterate over a block of code until the test expression is false, but sometimes we wish to terminate the current iteration or even the whole loop without checking test expression. Just like while loop, "For Loop" is also used to repeat the program. When its return true, the flow of control jumps to the inner while loop. Python While Loops Previous Next Python Loops. Flowchart of while Loop Flowchart for while loop in Python Example: Python while Loop Python while loop is used to run a code block for specific number of times. A sentinel value denotes the end of a data set, but it is not part of the data. With the while loop we can execute a set of statements as long as a condition is true. Previously, you learned how to write loops that read and process a sequence of values. Print i as long as i is less than 6: i = 1 while i 6: print(i) i += 1 The while loop is also useful in running a script indefinitely in the infinite loop. Python has two primitive loop commands: while loops; for loops; The while Loop. You must be careful to change the counter in a while loop, or you’ll get an infinite loop. The condition is true, and again the while loop is executed. In the nested-while loop in Python, Two type of while statements are available:Outer while loop; Inner while loop; Initially, Outer loop test expression is evaluated only once.. In Python, while loops are constructed like so: while [a condition is True]: [do something] The something that is being done will continue to be executed until the condition that is being assessed is no longer true. But unlike while loop which depends on … This is the basic syntax: While Loop (Syntax) These are the main elements (in order): The while keyword (followed by a space). If you already know the working of for Loop, then understanding the while Loop will be very easy for you. Leaving aside whether this loop is a good way to solve your larger problem, one reason your current while loop is not ever ending is because you've messed up the condition. We can use break and continue statements with while loop. The body starts with indentation and the first unindented line marks the end. Python interprets any non-zero value as True. Today you will learn about while loops with sentinel values. In Python, break and continue statements can alter the flow of a normal loop. This continues till x becomes 4, and the while condition becomes false. Let’s create a small program that executes a while loop. None and 0 are interpreted as False. How works nested while loop. While True → Loop will run forever unless we stop it because the condition of while is always True.. We can stop it using break statement. The else block with while loop gets executed when the while loop terminates normally. the inner while loop executes to completion.However, when the test expression is false, the flow of control … Sometimes you may want to use a ‘break’ statement to end the loop when a specific condition is met. Watch out for infinite loops when creating a program. If you delete the line counter = counter + 1 from our while loop, it will run forever: it never goes above 0, so the indented code runs over and over again. In this program, we’ll ask for the user to input a password. 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