Question

Java Program

Write a method called reverseBottomHalf that accepts a Stack of integers as a parameter and reverses only the values in the bottom half of the Stack. For example, if a Stack containing the values [1, 2, 3, 4, 5] were passed in (with 1 at the bottom and 5 at the top), the Stack would be changed to [2, 1, 3, 4, 5] (with 2 at the bottom and 5 at the top) after this method was called on it. You may only use one Queue as additional storage for this problem.

Answer 1

NOTE: FEEL FREE TO ASK ANY DOUBTS IN THE COMMENT SECTION

• HERE I DID NOT USED ANY QUEUES
• I SWAPPED STACK VALUES TO REVERSE VALUS USING INDEX
• IF YOU FIND THIS IS WRONG, PLEASE LET ME KNOW IN THE COMMENTS, I WILL EDIT CODE

CODE

Main.java

/* HERE i did not used any QUEUE
* I just swapped stack values at indexes
*/

import java.io.*;
// package for Stack class object
import java.util.*;

// Main Class which is public
public class Main
{
    // method to add array to stack
    static Stack<Integer> addArrayToStack(int[] array){
        // new stack for array values
        Stack<Integer> stack=new Stack<Integer>();

        // LOOP for all values in array
        for(int i=0;i<array.length;i++){
            // adding value to stack
            stack.add(array[i]);
        }
        // returning new stack
        return stack;
    }

    // Method to reverse Bottom half of stack
    static Stack<Integer> reverseBottomHalf(Stack<Integer> stack){
        // starting and half index of stack
        int start=0;
        int half=stack.size()/2;
        // LOOP for half of the hlaf values of stack
        for(int i=0;i<half/2;i++){
            // getting value at index i
            int newFirst=stack.get(i);
            // getting value at index from last of half
            int newLast=stack.get(half-i-1);
            // setting new values to stack
            stack.set(i,newLast);
            stack.set(half-i-1,newFirst);
        }
        // retuning updated stack
        return stack;
    }
    // main method to test above methods
   public static void main(String[] args) {
        // array1 for stack 1
       int[] arr1=new int[]{1,2,3,4,5};
       // array2 for stack 2
       int[] arr2=new int[]{1,2,3,4,5,6,7,8,9,10};

        // new stack for above two array values
        // calling method to insert array values to stacks
       Stack<Integer> stack1 = addArrayToStack(arr1);
       Stack<Integer> stack2 = addArrayToStack(arr2);

        // printing stack without reverse
       System.out.println("Stack1 without reverse: "+stack1);
       // calling method to reverse bottom half of stack1
       stack1 = reverseBottomHalf(stack1);
       // printing stack after reverse
       System.out.println("Stack1 after reverse: "+stack1);

        // printing stack without reverse
       System.out.println("Stack2 without reverse: "+stack2);
       // calling method to reverse bottom half of stack2
       stack2 = reverseBottomHalf(stack2);
       // printing stack after reverse
       System.out.println("Stack2 after reverse: "+stack2);
   }
}

OUTPUT in CONSOLE

Stackl without reverse: [1, 2, 3, 4, 5] Stacki after reverse: [2, 1, 3, 4, 5] Stack2 without reverse: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] Stack2 after reverse: (5, 4, 3, 2, 1, 6, 7, 8, 9, 10] ... Program finished with exit code o Press ENTER to exit console.

CODE in EDITOR

Main.java 1- /* HERE i did not used any QUEUE *I just swapped stack values at indexes 3 * 6 7 import java.io.*; // package for Stack class object import java.util.*; 9 // Main Class which is public 10 public class Main 11- { 12 // method to add array to stack 13 static Stack Integer> addArrayToStack(int[] array) { Il new stack for array values Stack<Integer> stack=new Stack<Integer>(); // LOOP for all values in array for(int i=0;i<array.length;i++){ // adding value to stack stack.add(array[i]); // returning new stack return stack; // Method to reverse Bottom half of stack static Stack<Integer> reverseBottomHalf(Stack Integer> stack) { // starting and half index of stack int start=0; int half-stack.size()/2; // LOOP for half of the hlaf values of stack for(int i=0;i<half/2;i++){ // getting value at index i int newFirst=stack.get(i); // getting value at index from Last of half int newLast=stack.get(half-i-1); // setting new values to stack

stack.set(i,newLast); stack.set(half-i-1, newFirst); // retuning updated stack return stack; // main method to test above methods public static void main(String[] args) { // array1 for stack 1 int[] arr1=new int[]{1,2,3,4,5}; // array2 for stack 2 int[] arr2=new int[]{1,2,3,4,5,6,7,8,9,10}; // new stack for above two array values Il calling method to insert array values to stacks Stack<Integer> stack1 = addArrayToStack(arr1); Stack Integer> stack2 = addArray ToStack(arr2); // printing stack without reverse System.out.println("Stack1 without reverse: "+stack1); I calling method to reverse bottom half of stackl stack1 = reverseBottomHalf(stack1); // printing stack after reverse System.out.println("Stack1 after reverse: "+stack1); // printing stack without reverse System.out.println("Stack2 without reverse: "+stack2); // calling method to reverse bottom half of stack2 stack2 = reverseBottomHalf stack2); // printing stack after reverse System.out.println("Stack2 after reverse: "#stack2); 70 }

PLEASE HELP ME by GIVING an UP VOTE

Thank YOU :-)