PROGRAMMING:A @ character rectangle

According to the n value read in, the character rectangle with @ as the filling character, 20 in width and N in height is output.
###Input format:
The input data has only one positive integer n (1 ≤ n ≤ 50). Output a character rectangle with @ as filling character, 20 in width and N in height.
###Output format:
Please describe the output format here.
###Input example:
Here is a set of inputs. For example:
```in
five
```
###Output example:
The corresponding output is given here. For example:
```out
@@@@@@@@@@@@@@@@@@@@
@@@@@@@@@@@@@@@@@@@@
@@@@@@@@@@@@@@@@@@@@
@@@@@@@@@@@@@@@@@@@@
@@@@@@@@@@@@@@@@@@@@
```







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