#encoding:utf-8

def NI(x,b): #定义求x关于b的逆元的函数NI,其中(NI(x,b)*x) mod b = 1 当x和b互质时求出的逆元唯一
  i = 1
  while (x*i)%b != 1:
    i = i + 1
  return i

c = "DBUHU SPANO SMPUS STMIU SBAKN OSMPU SS"
C = []

#对密文进行预处理并储存在列表中,储存形式是对应字母在26个英文字母中的位序
for i in c:
  if i == ' ':
    C.append(i)
  else:
    C.append(ord(i)-65)

#将加密算法中a可能的取值储存在列表中
a = [3,5,7,9,11,15,17,19,21,23,25]
P = []

for keyb in range(0,26):
  for keya in a:
    ni_a = NI(keya,26)
    for s in C:
      if s == ' ':
        P.append(' ')
      else:
        P.append(((s-keyb)*ni_a)%26) #将明文字母对应的位次码依次加入到明文列表中
    strP = ''
    for t in P:
      if t==' ':
        strP = strP + ' '
      else:
        strP = strP + chr(t+97) #将明文转化为字符串并输出
    print(strP)
    P = []