Goal
Given an ASCII art pattern, cast a shadow as if the light source is at top-left corner to make the pattern 3D-like.
Use hyphen (-) for darker shadow, and backtick (`) for lighter one.
Darker shadow is projected by shifting existing pattern 1 character down and 1 character right.
Lighter shadow is projected by shifting existing pattern 2 character down and 2 character right.
Input
Line 1: An integer N for the number of lines of the ASCII art pattern.
Next N lines: Lines of the ASCII art pattern.
Output
The processed pattern, with whitespace at the right trimmed, if any.
Example
Input
7
# #
# #
# #
#
# #
# #
# #
Output
# #
# # -
# # - `
# - `
# # `
# - #
# - ` #
- ` -
` `
