Leetcode Substring with concatenation of all Words

Topic Connection

https://leetcode.com/problems/substring-with-concatenation-of-all-words/

Substring with concatenation of all wordsdescription

You is given a string, s, and a list of words, words, that is all of the same length. Find all starting indices of substring (s) in S, a concatenation of each word in wordsexactly once and without any I ntervening characters.

For example, given:
S"barfoothefoobarman"
Words["foo", "bar"]

You should return the indices: [0,9] .
(Order does not matter).

According to test instructions Direct simulation (write very slow run Qaq)

Class Solution {public:    vector<int> findsubstring (string s, vector<string>& words) {        vector <int> Res;        if (S.empty () | | words.empty ()) return res;        for (auto &r:words) a[r]++;        int n = words[0].size (), M = S.size (), k = Words.size ();        int len = m-n * k + 1;        for (int i = 0; i < len; i++) {            int d = k, j = i;            B.clear ();            while (d) {                string temp = S.substr (j, N);                J + = N;                if (a.find (temp) = = A.end ()) {break                    ;                } else {                    b[temp]++;                    if (B[temp] > A[temp]) break;                    d--;                }            }            if (!d) res.push_back (i);        }        return res;    } Private:    map<string, int> A, B;};

Leetcode Substring with concatenation of all Words