C++ Program:

Example:

    *
  * * *
*       *

#include <iostream>
using namespace std;

int main() {
  int rows;
  cout <<"Enter number of rows: ";
  cin >> rows;
  for(int i=rows; i>=1; i--) {
    for(int j=1; j<=(2*rows-i); j++) {
      if(j==i||j==(2*rows-i)||(j>i && i==rows/2+rows%2))cout<<"* ";
      else cout<<"  ";
    }
    cout<<endl;
  }
  return 0;
}

Output:

Enter number of rows: 5

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

Main Logic :

for(int i=rows; i>=1; i--) {
  for(int j=1; j<=(2*rows-i); j++) {
    if(j==i||j==(2*rows-i)||(j>i && i==rows/2+rows%2))cout<<"* ";
    else cout<<"  ";
  }
  cout<<endl;
}

You can print any thing in this pattern, just replace your value with *