Learn while and do...while Loops | Building Conditions and Repetition

Imagine you are playing a game where you roll a standard six-sided die over and over, hoping to get a six. You keep rolling until you finally see that six appear. You do not know how many times you will have to roll—it might be the first try, or it might take several attempts. This is a lot like how a while loop works in JavaScript: it keeps repeating a block of code as long as a certain condition is true. When the condition changes (you roll a six), the loop stops.


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// Simulate rolling a die until a six appears using a while loop
let roll = 0;
while (roll !== 6) {
  roll = Math.floor(Math.random() * 6) + 1;
  console.log("You rolled a " + roll);
}
console.log("You finally rolled a six!");


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// Simulate rolling a die until a six appears using a do...while loop
let roll = 0;
do {
  roll = Math.floor(Math.random() * 6) + 1;
  console.log("You rolled a " + roll);
} while (roll !== 6);
console.log("You finally rolled a six!");

1. Which type of loop will always run its code at least once, even if the condition is false to begin with?

2. Fill in the blank to complete the while loop so it stops when `count` reaches `5`.

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Section 2. Chapter 4

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              1234567
            
// Simulate rolling a die until a six appears using a while loop
let roll = 0;
while (roll !== 6) {
  roll = Math.floor(Math.random() * 6) + 1;
  console.log("You rolled a " + roll);
}
console.log("You finally rolled a six!");


              1234567
            
// Simulate rolling a die until a six appears using a do...while loop
let roll = 0;
do {
  roll = Math.floor(Math.random() * 6) + 1;
  console.log("You rolled a " + roll);
} while (roll !== 6);
console.log("You finally rolled a six!");

1. Which type of loop will always run its code at least once, even if the condition is false to begin with?

2. Fill in the blank to complete the while loop so it stops when `count` reaches `5`.

Everything was clear?

Thanks for your feedback!

Section 2. Chapter 4

while and do...while Loops

1. Which type of loop will always run its code at least once, even if the condition is false to begin with?

2. Fill in the blank to complete the while loop so it stops when count reaches 5.

Awesome!

while and do...while Loops

1. Which type of loop will always run its code at least once, even if the condition is false to begin with?

2. Fill in the blank to complete the while loop so it stops when count reaches 5.

2. Fill in the blank to complete the while loop so it stops when `count` reaches `5`.

2. Fill in the blank to complete the while loop so it stops when `count` reaches `5`.