Test: Loops in JS - 1 - Software Development MCQ

The while loop in JavaScript repeatedly executes a block of code as long as the specified condition evaluates to true.

The do...while loop in JavaScript is similar to the while loop, but it guarantees that the code block will be executed at least once, even if the condition is initially false.

The break statement in JavaScript loops is used to exit the loop immediately, skipping the remaining iterations, and continues executing the code after the loop.

The continue statement in JavaScript loops is used to skip the current iteration and move to the next one, without executing the remaining code within the loop for that iteration.

An infinite loop in JavaScript is a loop that repeats indefinitely without a condition that can make it stop. It will keep executing the code block until the program is manually terminated or an error occurs.

The code uses a for loop to iterate from 0 to 4. The 'continue' statement is encountered when 'i' is equal to 3, which skips the current iteration. Therefore, the number 3 is omitted from the output.

The code uses a while loop to repeatedly output the value of 'i' until it becomes equal to or greater than 5. The initial value of 'i' is 0, and in each iteration, it is incremented by 2. Therefore, the output will be 0, 2, and 4.

The code uses a do...while loop to output the value of 'i' until it becomes equal to or greater than 3. The initial value of 'i' is 0, and in each iteration, it is incremented by 1. The loop continues until 'i' is no longer less than 3. Therefore, the output will be 0, 1, and 2.

The code uses a for loop to iterate from 0 to 'x - 1', where 'x' is initially set to 5. When 'i' becomes equal to 3, the 'break' statement is encountered, which terminates the loop immediately. Therefore, the output will be 0, 1, and 2.

The code uses a for loop to iterate from 0 to 'x - 1', where 'x' is initially set to 3. However, within the loop, the value of 'x' is incremented by 1 in each iteration. This causes the termination condition 'i < x' to always be true, leading to an infinite loop.

The code uses a switch statement to match the value of 'x' against different cases. Since 'x' is 0, it matches the case labeled '0' and executes the corresponding code block, which outputs "Zero."

The code uses a switch statement to match the value of 'x' against different cases. Since there is no case labeled '2', the execution falls back to the 'default case', which outputs "Default."

The for loop is most appropriate when the number of iterations is known in advance because it allows you to initialize a loop variable, specify a termination condition, and update the loop variable all within the loop statement.

The do...while loop is most appropriate when the condition for termination is checked at the end of the loop because it guarantees that the loop block will be executed at least once before checking the termination condition.

If the update expression is omitted in a for loop, the loop will continue to execute indefinitely because there is no mechanism to change the loop variable and satisfy the termination condition.