C++ programme to print decreasing number pattern

//This programme is tested on visual studio 2012//
#include<iostream>
using namespace std;
void main()
{
int num,sum=1;
cout<<"------------------------------------------------------------------------------\n";
cout<<"This programme will print a specific decreasing number pattern on entering number greater than 1\n";
cout<<"------------------------------------------------------------------------------\n";
   do
   {
  
    cout<<"Enter num";
    cin>>num;
}
    while(num<=1);
    for(int i=1;i<=num;i++)
    {
      
          sum=1;
    
        for(int j=i;j<=num;j++)
       {
        
        cout<<sum<<" ";
       sum=sum+1;
        }
        cout<<endl;
      
    }
    cout<<"\n\n------------------------------------------------------------------------------\n";
    cout<<"Thank You for using.\n\nVisit http://bilalzahid22.blogspot.com/ for more\n";
  cout<<"\n------------------------------------------------------------------------------\n";

}