PROGRAMMING:Reverse output upper triangle character array
This problem requires the preparation of procedures, * * reverse * * output n lines from the specified lowercase English characters constitute the upper left triangle character array. If the character is lower than a during the display, please return to Z to continue the display
###Input format:
Input a positive integer n (1 ≤ n < 7) and a lowercase English character startchar in one line.
###Output format:
Reverse output n lines of the upper left triangle character array starting from the lowercase letter startchar. The format is shown in the output sample, where there is a space after each letter.
###Input example:
```in
4 x
```
###Output example:
```out
x w v u
t s r
q p
o
```
answer：If there is no answer, please comment
###Input format:
Input a positive integer n (1 ≤ n < 7) and a lowercase English character startchar in one line.
###Output format:
Reverse output n lines of the upper left triangle character array starting from the lowercase letter startchar. The format is shown in the output sample, where there is a space after each letter.
###Input example:
```in
4 x
```
###Output example:
```out
x w v u
t s r
q p
o
```
answer：If there is no answer, please comment