规律查找

#include <iostream>

using namespace std;

int main(void)
{
    int n;

    cin >> n;

    for (int i = 1; i <= n / 2 + 1; i++) {
        for (int j = 1; j <= (n / 2) + 1 - i; j++) {
            cout << ' ';
        }
        for (int j = 1; j <= 2 * i - 1; j++) {
            cout << "*";
        }
        cout << endl;
    }
    int j = n / 2;
    for (int i = 1; i <= n / 2; i++) {
        for (int j = 1; j <= i; j++) {
            cout << ' ';
        }
        for (int k = 1; k <= 2 * j - 1; k++) {
            cout << '*';
        }
        j--;
        cout << endl;
    }

    return 0;
}

曼哈顿距离

#include <iostream>

using namespace std;

int main(void)
{
    int n;

    cin >> n;

    // 曼哈顿距离
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (abs(i - n / 2) + abs(j - n / 2) <= n / 2) cout << '*';
            else cout << ' ';
        }
        cout << endl;
    }

    return 0;
}