Question

import java.util.Stack;
import java.util.Scanner;

class Main {
public static void main(String[] args)
   {
       Stack<Integer> new_stack = new Stack<>();/* Start with the empty stack */
       Scanner scan = new Scanner(System.in);
       int num;
       for (int i=0; i<10; i++){//Read values
           num = scan.nextInt();
           new_stack.push(num);
       }
       int new_k = scan.nextInt();
System.out.println(""+smallerK(new_stack, new_k));
   }

   
public static int smallerK(Stack s, int k) {
       //TODO: Find the number of elements in stack s that are smaller (in value) than k
       //Example: if s=[50, 20, 30, 40, 10[ and k=25, the method should return: 2
  

   }

}

Answer 1

Please find below the method implementation as per requirement with required comment in each line:

public static int smallerK(Stack s, int k) {

       int smallerKValue=0;//set number of smaller elements to 0

       Iterator stackValue = s.iterator(); ////use iterator to iterate through stack values

       while(stackValue.hasNext()) {//repeat while stack is not empty

                if((int) stackValue.next() <k) {//if value in stack is less than the passed value k

                                smallerKValue++;//increment the counter

                  }//end if

       }//end while when all elements are iterated

       return smallerKValue;//return the counted value

   }//end methor smallerK

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Full Program is as below:

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import java.util.Stack;

import java.util.Iterator;

import java.util.Scanner;

class Main {

public static void main(String[] args)

   {

       Stack<Integer> new_stack = new Stack<>();/* Start with the empty stack */

       Scanner scan = new Scanner(System.in);

       int num;

       for (int i=0; i<10; i++){//Read values

           num = scan.nextInt();

           new_stack.push(num);

       }

       int new_k = scan.nextInt();

System.out.println(""+smallerK(new_stack, new_k));

   }

  

public static int smallerK(Stack s, int k) {

       int smallerKValue=0;//set number of smaller elements to 0

       Iterator stackValue = s.iterator(); ////use iterator to iterate through stack values

       while(stackValue.hasNext()) {//repeat while stack is not empty

                if((int) stackValue.next() <k) {//if value in stack is less than the passed value k

                                smallerKValue++;//increment the counter

                  }//end if

       }//end while when all elements are iterated

       return smallerKValue;//return the counted value

   }//end method smallerK

}

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Screenshot is as below:

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Output is as below:

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Green texts are inputs, 10-100 are stack elements and 55 is k value. 5 is returned by smallerK method