pt = { 
  'A' => [[1,1],
  		  [1,1]],
  		  
  'B' => [[1],
          [1],
          [1],
          [1]],
          
  'C' => [[1,1,1,1]],
  
  'D' => [[0,1],
          [1,1],
          [1,0]],
          
  'E' => [[1,1,0],
          [0,1,1]],
          
  'F' => [[1,0],
          [1,1],
          [0,1]],
          
  'G' => [[0,1,1],
  		  [1,1,0]]
}

def pt_match(b, p, x, y, h, w)
	for dx in 0 .. (w-1)
		xx = x + dx
		if xx >= 8 then
			return false
		end
		
		for dy in 0 .. (h-1) do
			yy = y + dy
			if yy >= 8 then
				return false
			end
			
			if b[yy][xx] != p[dy][dx] then
				return false
			end
		end
	end
	
	return true
end

def mv_pat(b, p, h, w)
	x = 0
	while x < (8 - w) do
		y = 0
		while y < (8 - h) do
			if pt_match(b, p, x, y, h, w) then
				return true
			end
			y += 1
		end
		x += 1
	end
	return false
end

loop {
	b = []
	8.times {
		if (line = gets) == nil then
			exit
		end
		b.push line.chomp.split('').map(&:to_i)
	}

	pt.each { | key, d |
		h= d.size
		w = d[0].size
		
		if mv_pat(b, d, h, w) then
			puts key
			break
		end
	}
}