![](https://images2017.cnblogs.com/blog/1196970/201801/1196970-20180112170836004-4749944.png)
1 { 2 for (int i = 1; i <= 9; i++) 3 { 4 for (int j = 1; j <= i; j++) 5 { 6 Console.Write($"{j}*{i}={j*i} "); 7 8 } 9 Console.WriteLine(); 10 11 } 12 Console.WriteLine(); 13 { 14 for (int i = 9; i >=1; i--) 15 { 16 for (int j =1; j <=i; j++) 17 { 18 Console.Write($"{j}*{i}={j * i} "); 19 } 20 Console.WriteLine(); 21 } 22 } 23 }