题解 | #坐标移动#

#include <iostream>
#include <cstring>

using namespace std;

int main() {
    int n, sum = 1, i;
    cin >> n;

    sum = n * n * n;

    if (n % 2 == 1) {

        for (i = 0; i < (n / 2); i++) {
            cout << sum / n - (n / 2 - i) * 2  << "+";
        }

        cout  << sum / n;

        for (i = 1; i <= n / 2; i++) {
            cout << "+" << sum / n + i * 2;
        }

    } else {

        for (i = 1; i <= (n / 2); i++) {
            cout << sum / n - (n / 2 - i) * 2 - 1 << "+";
        }

        for (i = 0; i < n / 2 - 1; i++) {
            cout  << sum / n + 1 + i * 2  << "+";
        }
        cout  << sum / n + 1 + i * 2;

    }

    return 0;
}