```[[練習問題]]

a = 'abcdefghijklmnopqrstuvwxyz .,-'
s = 'qdq-gi.q-a ziatmxxitmdqibtqi-ustbi ri.qmoqrcxi.qbubu zir -ibtqi-qp-qaai ripmymsqkir -ibtqi-qy dmxi ri.cnxuoi rruoumxakir -ibtqiqzmobyqzbkii-q.qmxi -imyqzpyqzbi rixmeaki -puzmzoqai -i-qscxmbu zaimzpir -i btq-iymbbq-a;iz -iatmxximzgi.q-a zinqiuzimzgiemgipuao-uyuzmbqpimsmuzabir -ia. za -uzsiacotiimi.qbubu zj'
for i in xrange(1, len(a)):
candidate = ''
for e in s:
if e == ';':
candidate += ';'
else:
candidate += a[(a.find(e) + i) % len(a)]
if 'person' in candidate:
print candidate
break
for i in xrange(len(a)):
candidate = ''.join(';' if e==';' else a[(a.find(e) + i) % len(a)] for e in s)
if 'person' in candidate:
print candidate

#初心者用

# coding:utf-8

A = "abcdefghijklmnopqrstuvwxyz .,-abcdefghijklmnopqrstuvwxyz .,-"
B = "qdq-gi.q-a ziatmxxitmdqibtqi-ustbi ri.qmoqrcxi.qbubu zir -ibtqi-qp-qaai ripmymsqkir -ibtqi-qy dmxi ri.cnxuoi rruoumxakir -ibtqiqzmobyqzbkii-q.qmxi -imyqzpyqzbi rixmeaki -puzmzoqai -i-qscxmbu zaimzpir -i btq-iymbbq-a;iz -iatmxximzgi.q-a zinqiuzimzgiemgipuao-uyuzmbqpimsmuzabir -ia. za -uzsiacotiimi.qbubu zj"
G = []

for i in range(len(A)):
G.append(A[i:i + 1])

L = ["p", "e", "r", "s", "o", "n"]
for k in range(1,len(A)/2):
N = ""
for q in range(len(L)):
w = G.index(L[q])
N += G[w + k]
if N in B:
C = []
H = ""
for t in range(len(B)):
C.append(B[t:t + 1])
for y in range(len(B)):
if C[y] == ";":
H += ";"
else:
v = G.index(C[y])
H += G[v - k]
print H
```