题解 | 尼科彻斯定理

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int num = (n-1)*n+1;;
        StringBuilder builder = new StringBuilder();
        for (int i = 1; i <= n; i++) {
            builder.append(num).append("+");
            num +=2 ;
        }
        System.out.println(builder.substring(0, builder.length() - 1));
    }
}

完了第一反应就是这个，面向测试用例编程