问题：
有个内含单词的超大文本文件，给定任意两个单词，找出在这个文件中这两个单词的最短距离(相隔单词数)。如果寻找过程在这个文件中会重复多次，而每次寻找的单词不同，你能对此优化吗?
示例：
输入：words = ["I","am","a","student","from","a","university","in","a","city"], word1 = "a", word2 = "student" 输出：1 提示：
words.length <= 100000
思路：
查找这两个单词的位置，通过双指针定位。
代码：
class Solution:
def findClosest(self
, words
: List
[str], word1
: str, word2
: str) -> int:
ind1
= 0
ind2
= 0
dis
= 100000
for i
in range(len(words
)):
if word1
== words
[i
]:
ind1
= i
elif word2
== words
[i
]:
ind2
= i
if ind1
!= 0 and ind2
!= 0:
tmp
= abs(ind1
- ind2
)
if tmp
< dis
:
dis
= tmp
return dis
