C++ :

#include<iostream>
using namespace std;
int main()
{
	int n;
	cin>>n;
	for (int i=1; i<=n; i++)
	{
		for (int j=1; j<=n-i; j++) cout<<" ";
		for (int j=1; j<=2*i-1; j++) cout<<"*";
		cout<<endl;
	}
	for (int i=1; i<n; i++)
	{
		for (int j=1; j<=i; j++) cout<<" ";
		for (int j=1; j<=2*(n-i)-1; j++) cout<<"*";
		cout<<endl;
	}
	return 0;
}

Pascal :

var
 i,j,k,x:longint;
begin
 read(x);
 for i:=1 to x do
 begin
  for j:=1 to x-i do
   write(' ');
  for k:=1 to 2*i-1 do
   write('*');
  writeln;
 end;
  for i:=x-1 downto 1 do
 begin
  for j:=1 to x-i do
   write(' ');
  for k:=2*i-1 downto 1 do
   write('*');
  writeln;
 end;
end.