如何在C++中修复金字塔模型?

我正在尝试输出:

#include <iostream>
using namespace std;

int main() {
int number;
bool flag;

    do {
        cout << "\t\t\Menu\n";
        cout << "Enter a number between 6 and 12.\n";
        cin >> number;

        if (number > 5 && number < 13) {
            flag = true;
            for(int index = 1; index <= number; ++index) {

                //Loop for spaces.
                for(int spaces = index; spaces < number; ++spaces) {
                    cout << " ";
                }

                //Loop for numbers.
                int counter = index;
                int counter2 = 1;
                for(int index2 = 1; index2 <= (2 * index - 1); ++index2) {
                    if (counter > 0) cout << counter--;
                    else cout << ++counter2;
                }

                cout << "\n";
            }

        } else cout << "Enter a valid number!\n";

    } while (!flag);

return 0;
}

我的输出:

如何用适当的空格固定输出,我尝试用空格连接,但不适合,如何正确地适合它?