[DS] LD3 9./25. variants

/* Java Program to Implement Stack*/
    import java.util.*;

    /*  Class arrayStack  */
    class arrStack{
        protected int arr[];
        protected int top, size, len;

        /*  Constructor for arrayStack */
        public arrStack(int n){
            size = n;
            len = 0;
            arr = new int[size];
            top = -1;
        }

        /*  Function to check if stack is empty */
        public boolean isEmpty(){
            return top == -1;
        }

        /*  Function to check if stack is full */
        public boolean isFull(){
            return top == size -1 ;
        }

        /*  Function to get the size of the stack */
        public int getSize(){
            return len ;
        }

        /*  Function to check the top element of the stack */
        public int peek(){
            if( isEmpty() )
                throw new NoSuchElementException("Underflow Exception");
            return arr[top];
        }

        /*  Function to add an element to the stack */
        public void push(int i){
            if(top + 1 >= size)
                throw new IndexOutOfBoundsException("Overflow Exception");
            if(top + 1 < size )
                arr[++top] = i;
            len++ ;
        }

        /*  Function to delete an element from the stack */
        public int pop(){
            if( isEmpty() )
                throw new NoSuchElementException("Underflow Exception");
            len-- ;
            return arr[top--];
        }

        /*  Function to display the status of the stack */
        public void display(){
            System.out.print("\nSteks = ");
            if (len == 0){
                System.out.print("Tukss\n");
                return ;
            }
            for (int i = top; i >= 0; i--)
                System.out.print(arr[i]+" ");
            System.out.println();
        }

        /*  Elementu skaits [-100;100] */
        public void elCount(){
            System.out.print("\nSkaits = ");
            int skaits = 0;
            for (int i = top; i >= 0; i--)
                if (arr[i] >= -100 && arr[i] <= 100) {
                    skaits++;
                }
            System.out.print(skaits);
            System.out.println();
        }
    }

    /*  Class StackImplement  */
public class Ld3151rdb414 {

    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        System.out.println("Toms Škarsts RDBIO 151RDB414");
        System.out.println("25. variants\n");
        System.out.println("---------Vektoriala forma attelots steks---------");
        System.out.println("Ievadiet steka izmeru ");
        int n = scan.nextInt();

        /* Creating object of class arrayStack */
        arrStack stk = new arrStack(n);

        /* Perform Stack Operations */
        char ch;
        do{
            System.out.println("\nSteka operacijas");
            System.out.println("1. pievienot elementu");
            System.out.println("2. dzest elementu");
            System.out.println("3. augsejais elements");
            System.out.println("4. parbaudit vai steks ir tukss");
            System.out.println("5. parbaudit va isteks ir pilns");
            System.out.println("6. steka izmers");
            System.out.println("7. elementi, kas pieder [-100;100]");
            int choice = scan.nextInt();
            switch (choice)
            {
            case 1 :
                System.out.println("Ievadiet skaitli");
                try {
                    stk.push( scan.nextInt() );
                }
                catch (Exception e){
                    System.out.println("Kluda : " + e.getMessage());
                }
                break;
            case 2 :
                try{
                    System.out.println("Izdzestais elements = " + stk.pop());
                }
                catch (Exception e){
                    System.out.println("Kluda : " + e.getMessage());
                }
                break;
            case 3 :
                try{
                    System.out.println("Augsejais elements = " + stk.peek());
                }
                catch (Exception e){
                    System.out.println("Kluda : " + e.getMessage());
                }
                break;
            case 4 :
                System.out.println("Steks tukss = " + stk.isEmpty());
                break;
            case 5 :
                System.out.println("Steks pilns = " + stk.isFull());
                break;
            case 6 :
                System.out.println("Steka izmers = " + stk.getSize());
                break;
            case 7 :
                stk.elCount();
                break;
            default :
                System.out.println("Wrong Entry \n ");
                break;
            }
            /* display stack */
            stk.display();
            System.out.println("\nVai velaties turpinat? (Ievadiet J vai N) \n");
            ch = scan.next().charAt(0);
        } while (ch == 'J'|| ch == 'j');
        scan.close();
    }

}