Question

pls help, idk whats wrong with this

Add the reverse() method which reverses the content of array without using additional array and the rotate(k) method which rotates left the content of array without using additional array by k elements.

import java.util.*;

* Implementation of the ADT List using a fixed-length array.
*
* if insert is successful returns 1, otherwise 0;
* for successful insertion:
* list should not be full and p should be valid.
*
* if delete is successful returns 1, otherwise 0;
* for successful deletion:
* list should not be empty and p should be valid.
*/
public class proj2 implements list{
       // class Variables
protected int n, count;
protected int arr[];   

proj2(int k){ // List Constructor
count = 0;
n = k;
        //Allocate Space for array            
arr = new int[n+1];// index 0 is not used
}
public boolean isEmpty(){
return (count == 0);}
public boolean isFull (){
return (count == n);}
public int   length (){
return count;}

       // insert x at position p
       // for successful insertion:
       // list should not be full and p should be valid.
       //    valid p's are: p >= 1 and p <= count+1    
public int insert(int x, int p){
int i;
System.out.printf("\n Insert %4d at position %2d.", x, p);
if (isFull() || p < 1 || p > count + 1)
return 0;
        // Shift from position p to right
for (i = count ; i >= p ; i--)
arr[i+1] = arr[i];
        // end for
        // insert x at position p          
arr[p] = x;
count++; // increment no. of elements.
return 1; // successful insertion
} // end insert

       // delete x at position p
       // for successful deletion:
       // list should not be empty and p should be valid.
       //    valid p's are: p >= 1 and p <= count    
public int delete(int p){
System.out.printf("\n Delete element at position %2d.", p);
if ( isEmpty() || p < 1 || p > count)
return 0;
        // Shift from position p + 1 to left
for (int i = p ; i < count ; i++)
arr[i] = arr[i+1];
        // end for
count --; // decrement no. of elements
return 1; // successful deletion
}

       // sequential serach for x in the list
       // if successful return position of x in the list,
       // otherwise return 0;
public int serachx(int x){
System.out.printf("\n search for %4d", x);
        // complete the rest
return 1;
}
      
       // print list elements
public void printlist(){
int i;
System.out.print("\n List contents: ");
for (i = 1; i <= count; i++)
System.out.printf("%4d, ", arr[i]);
        // enf for
}
private static void reverse(int a[], int n)

{

for (int i = 0; i < n / 2; i++) // swapping the elements upto n/2 index
  
{
  
int k = a[i];
  
a[i] = a[n - i - 1];
  
a[n - i - 1] = k;
  
}

/*printing the reversed array*/

System.out.print("\nElements of array After the reversing : ");

for (int i = 0; i < n; i++) {
  
System.out.print(a[i]+ " ");
  
}

}

static void rotate(int a[], int n,int k) // method for rotating the elements left

{

System.out.print("\nAfter rotating "+ k +" index left the content of array : ");

for(int i=0;i<n;i++)
  
{
  
// a[i] = a[ ( i + k)%n ];
  
System.out.print( a[ ( i + k)%n ]+" "); // here we are taking nod n beacuse if our left rotaion ie. k value is greater than n then make it zero
  
}

}      

public static void main(String args[]) {
int j, m, k, p, x, s;
try{
Scanner inf = new Scanner(System.in);  
k = inf.nextInt(); // read list size
   // Create a List of type Integer of size n
proj2 lst = new proj2(k);          
  
   // read m elements and insert in the list
m = inf.nextInt(); // read no. of elements to insert
System.out.printf("\nInsert %2d elements in the list", m);
for(j = 1; j <= m; j++){
x = inf.nextInt(); // read x
p = inf.nextInt(); // read position
s = lst.insert(x, p); // insert x at position p
if (s == 1)
System.out.printf("\nInserting %d at position %d was successful", x, p);              
else
System.out.printf("\nInserting %d at position %d was not successful", x, p);
}// end for
System.out.printf("\n\nList content after inserting %d elements", m);
lst.printlist();
  
   // read m positions to delete from list
m = inf.nextInt(); // read no. positions to delete
System.out.printf("\n\nDelete %d elements from list", m);
for(j = 1; j <= m; j++){
p = inf.nextInt(); // read position
s = lst.delete(p);
if ( s == 1)
System.out.printf("\nDeleting element at position %2d was successful", p);
else
System.out.printf("\nDeleting element at position %2d was not successful", p);
}// end for
System.out.printf("\n\nList content after deleting %d elements.", m);
lst.printlist();
inf.close(); // close input file
lst.reverse(); // reverse array elements
System.out.printf("\n\nList content after reversing.");
lst.printlist();
k = inf.nextInt(); // read k for rotate
lst.rotate(k); // rotate left by k elements
System.out.printf("\n\nList content after rotating %d.", k);
lst.printlist();

} catch (Exception e) {System.out.print("\nException " + e + "\n");}
} // end main
}// end class listarr

Answer 1

ANSWER:-

CODE:-

import java.util.*;

/* Implementation of the ADT List using a fixed-length array.
*
* if insert is successful returns 1, otherwise 0;
* for successful insertion:
* list should not be full and p should be valid.
*
* if delete is successful returns 1, otherwise 0;
* for successful deletion:
* list should not be empty and p should be valid.
*/
public class Proj2{
       // class Variables
protected int n, count;
protected int arr[];

Proj2(int k){ // List Constructor
    count = 0;
    n = k;
            //Allocate Space for array          
    arr = new int[n+1];// index 0 is not used
}
public boolean isEmpty(){
   return (count == 0);
}
public boolean isFull (){
   return (count == n);
}
public int   length (){
    return count;
}

         // insert x at position p
         // for successful insertion:
         // list should not be full and p should be valid.
         //    valid p's are: p >= 1 and p <= count+1  
public int insert(int x, int p){
    int i;
    System.out.printf("\n Insert %4d at position %2d.", x, p);
    if (isFull() || p < 1 || p > count + 1)
      return 0;
            // Shift from position p to right
    for (i = count ; i >= p ; i--)
     arr[i+1] = arr[i];
            // end for
            // insert x at position p        
    arr[p] = x;
    count++; // increment no. of elements.
    return 1; // successful insertion
} // end insert

         // delete x at position p
         // for successful deletion:
         // list should not be empty and p should be valid.
         //    valid p's are: p >= 1 and p <= count  
public int delete(int p){
    System.out.printf("\n Delete element at position %2d.", p);
    if ( isEmpty() || p < 1 || p > count)
      return 0;
            // Shift from position p + 1 to left
    for (int i = p ; i < count ; i++)
      arr[i] = arr[i+1];
            // end for
    count --; // decrement no. of elements
    return 1; // successful deletion
}

         // sequential serach for x in the list
         // if successful return position of x in the list,
         // otherwise return 0;
public int serachx(int x){
    System.out.printf("\n search for %4d", x);
    for(int i=1;i<=count;i++){
      if(arr[i] == x){
        return i;
      }
    }
    return 0;
}
      
         // print list elements
public void printlist(){
    int i;
    System.out.print("\n List contents: ");
    for (i = 1; i <= count; i++)
      System.out.printf("%4d, ", arr[i]);
    System.out.println();
          // enf for
}
private void reverse(int a[])

{

    for (int i = 1; i <= count / 2; i++) // swapping the elements upto n/2 index
    
    {
      int k = a[i];
      
      a[i] = a[count - i+1];
      
      a[count - i+1] = k;
    }
}

void rotate(int k) // method for rotating the elements left

{

    System.out.print("\nAfter rotating "+ k +" index left the content of array : ");

    while(k-->0){
      int i;
      int temp = arr[1];
      for(i=1;i<count;i++){
        arr[i] = arr[i+1];
      }
      arr[i] = temp;
    }

}    

public static void main(String args[]) {
    int j, m, k, p, x, s;
    try{
      Scanner inf = new Scanner(System.in);
      k = inf.nextInt(); // read list size
         // Create a List of type Integer of size n
      Proj2 lst = new Proj2(k);        
      
         // read m elements and insert in the list
      m = inf.nextInt(); // read no. of elements to insert
      System.out.printf("\nInsert %2d elements in the list", m);
      for(j = 1; j <= m; j++){
        x = inf.nextInt(); // read x
        p = inf.nextInt(); // read position
        s = lst.insert(x, p); // insert x at position p
        if (s == 1)
          System.out.printf("\nInserting %d at position %d was successful", x, p);            
        else
         System.out.printf("\nInserting %d at position %d was not successful", x, p);
      }// end for
      System.out.printf("\n\nList content after inserting %d elements", m);
      lst.printlist();
      
         // read m positions to delete from list
      m = inf.nextInt(); // read no. positions to delete
      System.out.printf("\n\nDelete %d elements from list", m);
      for(j = 1; j <= m; j++){
        p = inf.nextInt(); // read position
        s = lst.delete(p);
        if ( s == 1)
         System.out.printf("\nDeleting element at position %2d was successful", p);
        else
         System.out.printf("\nDeleting element at position %2d was not successful", p);
      }// end for
      System.out.printf("\n\nList content after deleting %d elements.", m);
      lst.printlist();
      //inf.close(); // close input file
      lst.reverse(lst.arr); // reverse array elements
      System.out.printf("\n\nList content after reversing.");
      lst.printlist();
      k = inf.nextInt(); // read k for rotate
      lst.rotate(k); // rotate left by k elements
      System.out.printf("\n\nList content after rotating %d.", k);
      lst.printlist();

    } catch (Exception e) {
      System.out.print("\nException " + e + "\n");
    }
} // end main
}

NOTE:- I implemented both reverse and rotate methods in your code.please check once.

If you need any modifications in the code,please comment below.Please give positive rating. THUMBS UP.

                THANK YOU!!!

OUTPUT:-