https://discuss.leetcode.com/topic/30941/here-is-a-10-line-template-that-can-solve-most-substring-problems
总结的还是不错的:
int findSubstring(string s){ vector<int> map(128,0); int counter; // check whether the substring is valid int begin=0, end=0; //two pointers, one point to tail and one head int d; //the length of substring for() { /* initialize the hash map here */ } while(end<s.size()){ if(map[s[end++]]-- ?){ /* modify counter here */ } while(/* counter condition */){ /* update d here if finding minimum*/ //increase begin to make it invalid/valid again if(map[s[begin++]]++ ?){ /*modify counter here*/ } } /* update d here if finding maximum*/ } return d; }