Question

Consider the following method. public static ArrayList<Integer mystery(int n) ArrayList<Integer seg - new ArrayList<IntegerO; for (int k = n; k > 0; k--) seq.add(new Integer(k+3)); return seq What is the final output of the following Java statement? System.out.println(mystery(3)); a. [1,2,4,5) b. [2,3,4,5) c. [6,5,4,3] d. [7, 7, 8, 8] e. [7,8,9, 8) O

Answer 1

Solution:

(1)

Given,

public static ArrayList<Integer> mystery(int n){

ArrayList<Integer> seq = new ArrayList<Integer>();

for( int k = n; k >= 0; k --)

seq.add(new Integer(k+3));

return seq;

}

System.out.println(mystery(3));

The answer will be an option:

(c) [6, 5, 4, 3]

Explanation:

=>mystery(int n) is a method/function which takes an integer as its argument and returns list of integers.

=>seq is an array list.

=>We can see that for loop is executed n+1 time from k = n to k = 0 decrementing the value k by 1 each time.

=>seq.add(new Integer(k+3)) means adding integers into the array list based on the value of k.

=>Calling mystery(3), here n = 3 means loop will be executed from k = 3 to k = 0

=>k+3 for first iteration of for loop = 3+3 => 6

=>For second iteration, k = 2 => 2+3 =>5

=>For third iteration, k = 1 => 1+3 => 4

=>For fourth iteration k = 0 => 0+3 => 3

=>Hence values will be printed of array = [6, 5, 4, 3]

I have explained each and every part of first question only accroding to "HOMEWORKLIB RULES when multiple questions are given then first answer is needed to be answered" with the help of statements attached to it.