For example,

Enter an odd integer

9

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

Write a C++ program that asks the user to input an odd integer value (>=5). Your program produces a diamond enclosed by a square of the given size.

First, you should open a new topic for this question and not just write in an existing one.
Second, you actually didn't ask a question
Third, don't you have any idea how to solve it? Or do you already have any skills in C++?

(solves "first" by using his mod-powers)

Have fun with the code and I hope, it'll be useful for you

#include <iostream>

using namespace std;

int plotdiamond(int links, int rechts, int max)
{
	cout << "*";
	for(int i = 2; i < max; i++)
	{
		if(i == links || i == rechts)
		{
			cout << "*";
		}
		else
		{
			cout << " ";	
		}
	}
	cout << "*" << endl;
}

int plotdiamond(int max)
{
	for(int i = 1; i <= max; i++)
	{
		cout << "*";	
	}
	cout << endl;
}

int main()
{
	int first, input, xl, xr;
	bool change = false;

	cout << "Insert an odd integer value:";
	cin >> input;

	first = (input+1)/2;
	xl = first;
	xr = first;

	plotdiamond(input);

	for(int i = 1; i < input-1; i++)
	{
		if(xl-1 == -1 || xr+1 == input+1 || change == true)
		{
			change = true;
			plotdiamond(++xl, --xr, input);
		}
		else
		{
			plotdiamond(--xl, ++xr, input);
		}
	}

	plotdiamond(input);
}