题解 | #尼科彻斯定理#

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;

public class Main {
    public static void main(String[] args) throws ParseException {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            int m = sc.nextInt();
            printOddNumber(m);
        }
        sc.close();
    }

    private static void printOddNumber(int m) {
        int sum = (int) Math.pow(m, 3);
        if (m == 1) {
            System.out.println(1);
        }
        int mid = sum / m;
        if (mid % 2 == 0) {
            for (int i = m / 2; i > 0; i--) {
                int n = mid - i * 2 + 1;
                System.out.print(n + "+");
            }
            for (int i = 1; i < m / 2 + 1; i++) {
                int n = mid + i * 2 - 1;
                if (i == m / 2) {
                    System.out.print(n);
                } else {
                    System.out.print(n + "+");
                }
            }
        } else {
            for (int i = m / 2; i > 0; i--) {
                int n = mid - i * 2;
                System.out.print(n + "+");
            }
            System.out.print(mid + "+");
            for (int i = 1; i < m / 2 + 1; i++) {
                int n = mid + i * 2;
                if (i == m / 2) {
                    System.out.print(n);
                } else {
                    System.out.print(n + "+");
                }
            }
        }
    }
}