r=raw_input();print"".join(([[" ","","abc","def","ghi","jkl","mno","pqrs","tuv","wxyz"][ord(e[0])-48][len(e)-1]for e in r.split("1")[:-1]],[chr(c+97) for c in range(26)])[r[9]=='3'])
Note that non-ascii characters in the above source code will be escaped (such as \x9f).