Loops and Arrays

What is a loop in programming?

A structure that repeats a set of instructions until a condition is met.

Name the main types of loops in Java.

while, do...while, for, for-each, and recursion (repetitive behaviour, not a true loop).

Which loop is considered the "monarch" of loops?

while loop — all other loops can be built from it.

What happens if a while loop has no terminating condition?

It becomes an infinite loop, causing the program to hang or crash.

When is the condition checked in a do...while loop?

At the end of the loop, after the body executes.

What does "once or more" mean in a do...while loop?

The loop runs at least once, even if the condition is false initially.

What is the main advantage of a for loop over a while loop?

It’s more concise when the number of iterations is known in advance.

What is the scope of the loop counter in a for loop?

It’s local to the loop body — cannot be used outside the loop.

What keyword is used to declare an array in Java?

new, as in new int[10].

What is the syntax to declare an integer array of length 10?

int[] numberStore = new int[10];

What type of values can an array hold?

Primitives or objects, depending on how it's declared.

What error is thrown if an invalid array index is accessed?

ArrayIndexOutOfBoundsException.

How can you avoid going out of bounds in an array?

Use a for loop with the condition i < array.length.

What does the “for each” loop simplify?

Iterating through all elements in an array or collection.

What is the syntax of a for each loop?

for (dataType element : array) { // code }

Can you modify array elements using a for each loop?

No — it provides read-only access to the values.

What limitation does the for each loop have compared to for?

You can't access the index of the current element directly.

Why do arrays use special syntax in Java?

Because they are objects but don’t use constructors directly.

What is a real-world analogy for arrays in Java?

If a variable is a cup, an array is a shelf of cups.