从键盘输入1个正整数n(1<=n<=10)，要求用矩阵形式输出n以内的加法口诀表，要求如下：

 1 import java.util.*;
 2 public class Main {
 3     public static void main (String [] args) {
 4         Scanner scan=new Scanner(System.in);
 5         int n=scan.nextInt();
 6         System.out.print("+ ");
 7         for(int i=1;i<=n;i++) {
 8             System.out.print(i+" ");            
 9         }
10         System.out.println();
11         for(int j=1;j<=n;j++) {
12             System.out.print(j+" ");
13             for(int k=1;k<=j;k++) {
14                 System.out.print(j+k+" ");    
15             }
16             System.out.println();
17         }
18     }
19 }