P87198: Octàgons facilets

#include <iostream>
using namespace std;


//Pre: Llegeix diversos naturals >= 2
//Post: Escriu un octàgon de mida n
int main() {
    int n;
    while (cin >> n) {
        int ce = n-1, cx = n; //Comparador espais ce i comparador x cx
        for (int s = n-1; s != 0; --s) { //Files superiors
            for (int e = ce; e != 0; --e) {
                cout << ' ';
            }
            for (int x = cx; x != 0; --x) {
                cout << 'X';
            }
            cout << endl;
            cx = cx + 2;
            --ce;
        }
        for (int s = n; s != 0; --s) { //Files centrals
            for (int e = cx; e != 0; --e) {
                cout << 'X';
            }
            cout << endl;
        }
        cx = cx - 2;
        ce = 1;
        for (int s = n-1; s != 0; --s) { //Files inferiors
            for (int e = ce; e != 0; --e) {
                cout << ' ';
            }
            ++ce;
            for (int x = cx; x != 0; --x) {
                cout << 'X';
            }
            cx = cx -2;
            cout << endl;
        }
        cout << endl;
        }
}