检索每个字符串的子串（python散列表实现）

import re

def get_str(i,num):
    str_list = re.findall(r'.{{{str_length}}}'.format(str_length=i), num)
    return str_list

def add_str(res,i,str_list):
    if res.get(i):
        res[i] += str_list
    else:
        res.update({i: str_list})
    return res

data = map(int, raw_input().strip().split())
n, q = data[0], data[1]

books={}
reader={}
for i in range(0,n):
    book = {}
    num=str(raw_input().strip())
    length=len(num)
    book = add_str(book, length, [num])
    for item_len in range(1,length):
        length_temp=item_len
        for j in range(0,length_temp):
            str_list = get_str(item_len, num[j:])
            book=add_str(book,item_len, str_list)
    books.update({i:book})
# print books
result=[]
for i in range(0,q):
    num=raw_input().strip()
    length,name=num.split()
    length=int(length)
    book_list = books[i].get(length, [])
    #print name,book_list
    if name in book_list:
        result.append(name)
    else:
        result.append('-1')
for i in result:
    print i