package demo1;public class Demo {    public static void main(String[] args)     {        int a=4;        for(int i=1;i<=a;i++)        {            for(int k=1;k<=a-i;k++)            {                System.out.print(" ");            }            for(int j=1;j<=(i-1)*2+1;j++)            {                System.out.print("*");            }            System.out.println();        }            }}

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package demo1;public class Demo {    public static void main(String[] args)     {        int a=4;        for(int i=1;i<=a;i++)        {            for(int k=1;k<=a-i;k++)            {                System.out.print(" ");            }            for(int j=1;j<=(i-1)*2+1;j++)            {                if(i==1||i==a)                {                System.out.print("*");                }                else                {                    if( j==1||j==(i-1)*2+1)                    {                        System.out.print("*");                    }                    else                    {                        System.out.print(" ");                    }                                        }            }            System.out.println();        }            }}

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