Try This

Code:
#include <iostream>
#define MAX  5
int main()
{
for ( int i = 1; i <= MAX; ++i)
{
  for(int k=0;k<MAX-i;k++)
     {
             std::cout<<" ";
     }
  for ( int j = 1; j <= i; ++j )
     std::cout << "**";
     std::cout << "\n";
}
return 0;
}