hollowbutterflypattern.cpp

#include<iostream>
using namespace std;

int main()
{
    int i,j,n;
    cout<<"Enter the number: ";
    cin>>n;
    for(i=1;i<=n;i++)
          {
            for(j=1;j<=i;j++)
              {
                if(j==1||j==i)
                   {
                     cout<<"*";
                   }
                else
                {
                  cout<<" ";
                }
                 
              }
            for(j=1;j<=n-i;j++)
                {
                  cout<<" ";
                } 
            for(j=1;j<=n-i;j++)
                {
                  cout<<" ";
                }
            for(j=i;j>=1;j--)
                {
                    if(j==1||j==i)
                         {
                           cout<<"*";
                         }
                    else
                    {
                      cout<<" ";
                    }
                    
                }             
            cout<<endl;
          }
     for(i=n;i>=1;i--)
          {
            for(j=1;j<=i;j++)
              {
                if(j==1||j==i)
                   {
                     cout<<"*";
                   }
                else
                {
                  cout<<" ";
                }
                 
              }
            for(j=1;j<=n-i;j++)
                {
                  cout<<" ";
                } 
            for(j=1;j<=n-i;j++)
                {
                  cout<<" ";
                }
            for(j=i;j>=1;j--)
                {
                    if(j==1||j==i)
                         {
                           cout<<"*";
                         }
                    else
                    {
                      cout<<" ";
                    }
                    
                }             
            cout<<endl;
          }
    return 0;
}