Question

Using a loop and indexed addressing, write code that rotates the members of a 32-bit integer array forward one position. The value at the end of the array must wrap around to the ?rst position. For example, the array [10,20,30,40] would be transformed into [40,10,20,30].

Answer 1

//begin class definition

public class Rotator{

//main method to execute the program

public static void main(String []args){

//create and initialize an array with hypothetical values

int [] arr = {10, 20, 30, 40};

//create a new array that will hold the rotated values

//it should have the same length as the original array

int [] new_arr = new int[arr.length];

//loop through the original array up until the

//penultimate value which is given by 'arr.length - 1'

for(int i = 0; i < arr.length - 1; i++ ){

//at each cycle, put the element of the

//original array into the new array

//one index higher than its index in the

//original array.

new_arr[i + 1] = arr[i];

}

//Now put the last element of the original array

//into the zeroth index of the new array

new_arr[0] = arr[arr.length - 1];

//print out the new array in a nice format

System.out.print("[ ");

for(int j = 0; j < new_arr.length; j++){

System.out.print(new_arr[j] + " ");

}

System.out.print("]");

}

}

Sample Output:

[ 40 10 20 30 ]

Step-by-step explanation:

The code above is written in Java. It contains comments explaining important parts of the code. A sample output has also been provided.