s=input().split() a=(s[0]) b=(s[1]) c=(s[2]) d=(s[3]) if a=="z": print("a",end=" ") else: j=ord(a)+1 print(chr(j),end=" ") if b=="z": print("a",end=" ") else: j=ord(b)+1 print(chr(j),end=" ") if c=="z": print("a",end=" ") else: j=ord(c)+1 print(chr(j),end=" ") if d=="z": print("a",end=" ") else: j=ord(d)+1 print(chr(j),end=" ")