題目來自leetcode
All DNA is composed of a series of nucleotides abbreviated as A, C, G, and T, for example: "ACGAATTCCG". When studying DNA, it is sometimes useful to identify repeated sequences within the DNA.
Write a function to find all the 10-letter-long sequences (substrings) that occur more than once in a DNA molecule.
For example,
Given s = "AAAAACCCCCAAAAACCCCCCAAAAAGGGTTT",
Return:
["AAAAACCCCC", "CCCCCAAAAA"].
題目的意思就是如何在一個字符串中找到出現(xiàn)不只一次且長度大于10的字串,python的代碼旺垒，超簡單- -
class Solution:
# @param s, a string
# @return a list of strings
def findRepeatedDnaSequences(self, s):
rs = []
keep = set()
for i in range(len(s)):
temp = s[i + 0:i + 10]
if temp in keep:
if temp not in rs:
rs.append(temp)
else:
keep.add(temp)
return rs
主要應用了堆查找速度為1的特性- -
