How to find a single cell in a 2D array?

Ruby
1

I have defined a method to read any one of multiple maze files.

maze = []
def maze_reader
mz_file = File.open(“maze1.mz”)
while ! mz_file.eof?
line = mz_file.gets.chomp.split(" ")
maze << line
end
mz_file.close

Next I need to create a method to find specific letters in the maze, say
S for start and F for finish.

I have listened to tutorials; however, I have a learning problem that
often prevents me from memorizing spoken words, and the book I am using
does not appear to cover this yet.
Is there anyone who can point me in the right direction?

2

This will find the first matching location in a 2D array of Strings.

maze = [[‘S’,’ ‘,’ ‘],[’ ‘,’ ‘,’ ‘],[’ ‘,’ ',‘F’]]

def find_location( maze, location )

Go through each row

maze.each_index do |i|
# Find the location in the row
result = maze[i].index( location )
# Return the row index and location index if found
return [i, result] if result
end

return nil if nothing was found

return nil
end

find_location maze, ‘S’
=> [0, 0]
find_location maze, ‘F’
=> [2, 2]

3

class Array
def rfind(sae,aa=[])
each_with_index() { |a,i|
r= a.kind_of?(Array) ? a.rfind(sae,aa+[i]) : a==sae ? aa+[i] :
false
return r if r
}
nil
end
end

a=[1,2,3,4]
p a.rfind(3)
p a.rfind(9)

a=[
[1,2,3,4],
[1,2,3,4],
[1,2,3,4],
[1,9,3,4],
[1,2,3,4],
]
p a.rfind(9)

a=[
[[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4],],
[[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4],],
[[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4],],
[[1,2,3,4],[1,2,3,4],[1,2,9,4],[1,2,3,4],[1,2,3,4],],
]
p a.rfind(9)

==
[2]
nil
[3, 1]
[3, 2, 2]