local ffi = require 'ffi'
local C, ct = ffi.C, ffi.typeof 'uint8_t[1]'
ffi.cdef 'int scanf(const char *, ...);'

io.write((function (h, w, c)
	local a={}
	for i=1,3 do C.scanf("%u%u",h,w) a[i]={string.char(c+i),h[0],w[0]} end
	table.sort(a, function (a,b) return a[2]==b[2] and a[3]<b[3] or a[2]>b[2] end)
	return a[1][1],"\n",a[2][1],"\n",a[3][1],"\n"
end)(ct(), ct(), string.byte("A")-1))