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Java Exercises: Rotate an array of integers in left direction

Java Basic: Exercise-79 with Solution

Write a Java program to rotate an array (length 3) of integers in left direction.
Test Data: {20, 30, 40}
Expected output: {30, 40, 20}

Sample Solution:

Java Code:

import java.util.Arrays; 
 public class Exercise79 {
 public static void main(String[] args)
 {
    int[] array_nums = {20, 30, 40};
	System.out.println("Original Array: "+Arrays.toString(array_nums)); 
	int[] new_array_nums = {array_nums[1], array_nums[2], array_nums[0]};
	System.out.println("Rotated Array: "+Arrays.toString(new_array_nums)); 	 
 }
}

Sample Output: 

Original Array: [20, 30, 40]                                           
Rotated Array: [30, 40, 20]

Pictorial Presentation:

Java exercises: Rotate an array of integers in left direction

Flowchart:

Flowchart: Java exercises: Rotate an array of integers in left direction

Java Code Editor:

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Next: Write a Java program to get the larger value between first and last element of an array (length 3) of integers.

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Java: Tips of the Day

Try and catch:

Java is excellent at catching errors, but it can only recover gracefully if you tell it what to do. The cascading hierarchy of attempting to perform an action in Java starts with try, falls back to catch, and ends with finally. Should the try clause fail, then catch is invoked, and in the end, there's always finally to perform some sensible action regardless of the results. Here's an example:

try {
        cmd = parser.parse(opt, args); 
       
        if(cmd.hasOption("help")) {
                HelpFormatter helper = new HelpFormatter();
                helper.printHelp("Hello ", opt);
                System.exit(0);
                }
        else {
                if(cmd.hasOption("shell") || cmd.hasOption("s")) {
                String target = cmd.getOptionValue("tgt");
                } // else
        } // fi
} catch (ParseException err) {
        System.out.println(err);
        System.exit(1);
        } //catch
        finally {
                new Hello().helloWorld(opt);
        } //finally
} //try

It's a robust system that attempts to avoid irrecoverable errors or, at least, to provide you with the option to give useful feedback to the user. Use it often, and your users will thank you!

Ref: https://red.ht/3EZc9OC