Dynamic_Stack_Implementation

package ds.Dynamic_Stack;

public class Runner {

public static void main(String[] args)
{
  Stack stack = new Stack();
  stack.size();
  stack.push(10);
  stack.size();
  stack.push(10);
  stack.size();
  stack.push(10);
  stack.size();
  stack.push(10);
  stack.size();
  stack.push(10);
  stack.size();
  stack.size();
  stack.push(10);
  stack.size();
  stack.push(10);
  stack.size();
  stack.pop();
  stack.size();
  stack.pop();
  stack.pop();
  stack.size();
  stack.pop();
  stack.size();
  stack.pop();
  stack.pop();
  stack.pop();
  stack.pop();
  stack.pop();
  stack.pop();
  stack.pop();
  stack.size();

}

}

====================================================================

package ds.Dynamic_Stack;

public class Stack 

{

int[] stack = new int[2];

int  top = 0;

int capacity = 2;

public void push(int data) 

{

if(top == capacity)

expand();

stack[top] = data;

top++;

}

private void expand() 

{

System.out.println("Expanding");

int[] newStack = new int[capacity*2];

System.arraycopy(stack, 0, newStack, 0, stack.length);

stack = newStack;

capacity = capacity *2;

}

public void show() 

{

for(int n :stack)

System.out.print(n+" ");

}

public void pop() 

{

int data;

if(top<=0)

{

System.out.println("Stack is Empty");

return;

}

else

{

top--;

data  = stack[top];

stack[top]= 0;

shrink();

}

System.out.println("Popped Data: "+data);

}

private void shrink() 

{

System.out.println("Shrinked");

  int size = stack.length;

  if(size<capacity/2)

  {

  int s1 = capacity/2;

  int[] ShrinkedArray = new int[s1];

  System.arraycopy(stack, 0, ShrinkedArray, 0, stack.length);

  stack = ShrinkedArray;

  }

}

public int  peek() 

{

if(top<=0)

{

System.out.println("Stack is Empty");

return 0;

}

else

{

int data;

data  = stack[top -1];

return data;

}

}

public void size() 

{

  //return (top);

  System.out.println("Size: "+top);

}

public void  isEmpty() 

{

  if(top<=0)

  System.out.println("Stack is Empty");

  

  else

  System.out.println("Stack is NOT Empty");

  

}

}

===========================================================

Star Patterns

1. Star Pattern 1
2. Star Pattern 2
3. Star Pattern 3
4. Star Pattern 4
5. Star Pattern 5
6. Star Pattern 6
7. Star Pattern 7
8. Star Pattern 8
9. Star Pattern 9
10. Star Pattern 10
11. Star Pattern 11
12. Star Pattern 12
13. Star Pattern 13
14. Star Pattern 14
15. Star Pattern 15

StartPattern14

package interview;
/*

 *     *
  *   *
   * *
    *
    *
   * *
  *   *
 *     *

*/
public class StartPattern14 {

public static void main(String[] args)
{
  for(int i =0;i<5;i++)
  {
  for(int j=0;j<5;j++)
  {
  if(i==j || i+j== 5-1)
  {
  System.out.print("*");
  }else
  {
  System.out.print(" ");
  }
 
  }
  System.out.println();
  }

}

}

StarPattern15

package interview;
/*

*****
*   *
*   *
*   *
*****


*/public class StarPattern15 {

public static void main(String[] args)
{
for(int i =0;i<14;i++)
  {
  for(int j=0;j<14;j++)
  {
  if(i==0 || i==14-1 ||j==0 ||j==14-1)
  {
  System.out.print("*");
  }else
  {
  System.out.print(" ");
  }  
  }
  System.out.println();
  }

}

}

StarPattern13

package interview;
/*

 *     *
  *   *
   * *
    *
    *
   * *
  *   *
 *     *

*/

public class StarPattern13 {

public static void main(String[] args)
{
for(int i = 4;i>=1;i--)
  {
  for(int j = 5;j>i;j--)
  {
  System.out.print(" ");
  }
 
  for(int j = 1;j<(i*2);j++)
  {
if(j>1 && j<(i*2)-1)
{
System.out.print(" ");
}else
{
System.out.print("*");
}  
  }
  System.out.println();
  }
//-----
for(int i = 1 ;i<=4;i++)
  {
  for(int j = 4;j>=i;j--)
  {
  System.out.print(" ");
  }
  for(int j = 1;j<(i*2);j++)
  {
if(j>1 && j<(i*2)-1)
{
System.out.print(" ");
}else
{
System.out.print("*");
}  
  }  
  System.out.println();
  }

}

}

StarPattern12

package interview;
/*
    *
   ***
  *****
 *******
*********
 *******
  *****
   ***
    *
*/

public class StarPattern12 {

public static void main(String[] args)
{

  for(int i = 1 ;i<=5;i++)
  {
  for(int j = 5;j>i;j--)
  {
  System.out.print(" ");
  }
  for(int j = 1;j<=i;j++)
  {
  System.out.print("*");
  }
  //-----------
  for(int j =2;j<=i;j++)
  {
  System.out.print("*");
  }
 
  System.out.println();
  }
//-----------below triangle
  for(int i = 1;i<5;i++)
  {
  for(int j = 0;j<i;j++)
  {
  System.out.print(" ");
  }
  for(int j = 5;j>i;j--)
  {
  System.out.print("*");
  }
  for(int j = 4;j>i;j--)
  {
  System.out.print("*");
  }
  System.out.println();
  }

}

}

StarPattern11

package interview;
/*
     *
    * *
   *   *
  *     *
 *       *
  *     *
   *   *
    * *
     *
*/
public class StarPattern11 {

public static void main(String[] args)
{
  for(int i = 1 ;i<=5;i++)
  {
  for(int j = 4;j>=i;j--)
  {
  System.out.print(" ");
  }
  for(int j = 1;j<(i*2);j++)
  {
if(j>1 && j<(i*2)-1)
{
System.out.print(" ");
}else
{
System.out.print("*");
}  
  }  
  System.out.println();
  }
//-----------below triangle
  for(int i = 4;i>=1;i--)
  {
  for(int j = 5;j>i;j--)
  {
  System.out.print(" ");
  }
 
  for(int j = 1;j<(i*2);j++)
  {
if(j>1 && j<(i*2)-1)
{
System.out.print(" ");
}else
{
System.out.print("*");
}  
  }
  System.out.println();
  }

}

}