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Java Exercises: Swap the first and last elements of an array and create a new array

Java Basic: Exercise-81 with Solution

Write a Java program to swap the first and last elements of an array (length must be at least 1) and create a new array.

Sample Solution:

Java Code:

import java.util.Arrays; 
 public class Exercise81 {
 public static void main(String[] args)
 {
    int[] array_nums = {20, 30, 40};
	System.out.println("Original Array: "+Arrays.toString(array_nums)); 
	int x = array_nums[0];
	array_nums[0] = array_nums[array_nums.length-1];
	array_nums[array_nums.length-1] = x;
	System.out.println("New array after swaping the first and last elements: "+Arrays.toString(array_nums));  
 }
}

Sample Output:

Original Array: [20, 30, 40]                                           
New array after swaping the first and last elements: [40, 30, 20]

Flowchart:

Flowchart: Java exercises: Swap the first and last elements of an array and create a new array

Java Code Editor:

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Previous: Write a Java program to get the larger value between first and last element of an array (length 3) of integers.
Next: Write a Java program to find the largest element between first, last, and middle values from an array 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
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} 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