Multiple Choice Questions on For Loops and Arrays in Java

📚 Quick Study Guide

🔍 For Loops: Used for executing a block of code repeatedly. Syntax: `for (initialization; condition; increment/decrement) { // code }` ➕ Initialization: Executed only once at the beginning of the loop. Typically declares and initializes a counter variable. 📐 Condition: Evaluated before each iteration. The loop continues as long as the condition is true. ➗ Increment/Decrement: Executed after each iteration. Modifies the counter variable. 📜 Arrays: A collection of elements of the same data type stored in contiguous memory locations. Accessed using an index (starting from 0). 🧮 Array Declaration: `dataType[] arrayName = new dataType[arraySize];` 🧰 Accessing Elements: `arrayName[index]`. Remember index ranges from 0 to `arraySize - 1`. 💥 `ArrayIndexOutOfBoundsException`: Thrown if you try to access an element outside the valid index range.

Practice Quiz

1. Which of the following is the correct syntax for a `for` loop in Java?
   1. for (i = 0; i < 10; i++)
   2. for (int i = 0; i < 10;)
   3. for (i < 10; i++)
   4. for (int i = 0; i < 10; i++)
2. What will be the output of the following code?

   int[] arr = {1, 2, 3, 4, 5};
     System.out.println(arr[2]);

   1. 1
   2. 2
   3. 3
   4. 4
3. What happens if you try to access an array element with an index that is out of bounds?
   1. The program will compile and run, but might produce unexpected results.
   2. The program will throw an `ArrayIndexOutOfBoundsException`.
   3. The program will compile, but crash during runtime.
   4. The program will automatically resize the array.
4. Which of the following statements correctly initializes an array of 5 integers?
   1. int[] arr = new int[5];
   2. int arr = new int[5];
   3. int arr[] = new int[4];
   4. int arr[] = new int[];
5. What is the purpose of the `length` property of an array in Java?
   1. It returns the number of elements currently stored in the array.
   2. It returns the maximum number of elements that can be stored in the array.
   3. It returns the index of the last element in the array.
   4. It sets the number of elements in the array.
6. What will be the output of the following code snippet?

   for (int i = 5; i > 0; i--) {
     System.out.print(i + " ");
     }

   1. 1 2 3 4 5
   2. 0 1 2 3 4
   3. 5 4 3 2 1
   4. 4 3 2 1 0
7. Which loop is best suited for iterating through all the elements of an array?
   1. while loop
   2. do-while loop
   3. for loop
   4. if-else statement