leetcode187. Repeated DNA Sequences

https://leetcode.com/problems/repeated-dna-sequences/#/description

 

https://leetcode.com/problems/repeated-dna-sequences/#/solutions

 

位运算大法好

值得注意 例如0xff 一个f表示15 二进制中表示1111

 

 class Solution {
 public:
     vector<string> findRepeatedDnaSequences(string s) {
         //A is 0101, C is 0103, G is 0107, T is 0124       //3bit to store
         unordered_map<int,int> m;
         vector<string> r;
         int t=,i=,ss=s.length();
         while(i<)
           t=t<<|s[i++]&;
         while(i<ss)
           if(m[t=t<<&0x3fffffff|s[i++]&]++==)
             r.push_back(s.substr(i-,));
         return r;
     }
 };