Question

Which of the following are valid array declarations? a. int[] array- new int[10]; b. double [array double[10]; c. charl charArray "Computer Science"; None of the above Analyze the following code: class Test public static void main(Stringl] args) System.out.println(xMethod(10); public static int xMethod(int n) System.out.println("int"); return n; public static long xMethod(long n) System.out.,println("long"); return n The program displays int followed by 10 The program displays long followed by 10. The program does not compile. None of the above. tions 3-4 are based on the following method: e void nPrint(String message, int n) while (n> 0) System.out.print(message);

Answer 1

1) Answer: a) int[] array = new int[10];

a) It is valid array declaration because it is the standard syntax to declare an array.

b)It is invalid because it has no new keyword

c) It is invalid because a string cannot be converted into a char array.

2) Answer: The program displays int followed by 10

Explanation: In the main when the xMethod(10) is called it invokes the function static int xMethod(int) because the argument passed in the function call is of type integer but not long.

3) Answer:d) invalid call

Explanation: It gives an error because the function call has float in the second argument where it should be an integer. This results in lossy conversion. And shows an error.

nPrint("a",3.0);

4) Answer: c.3

EXPLANATION: nPrint() function was called using pass by value. So this does not effect the value of k in main(). It's value remains the same.

nPrint("A message",k);

5) Answer: a) the code has syntax error because I is not define before or in System.out.println("i is: +i");

Explanation: The scope of i is limited to the for block. So, i is an unknown symbol when it is used in System.out.println();

6) Answer: d

Explanation: Because the xMethod () doesn't have a return statement in it's definition.

7) Answer: a) The code prints n is 2

Explanation: The xMethod () is called using pass by value. So the change of n in function definition doendoe reflect in the value of n in the main(). So, the value of n remains same, 2.