Steward

分享是一種喜悅、更是一種幸福

程式語言 - LeetCode - C++ - 438. Find All Anagrams in a String

---

題目：


解答：

class Solution {
public:
    vector<int> findAnagrams(string s, string p) {
        vector<int> need(26);
        vector<int> window(26);

        for (char c : p) {
            need[c - 'a'] += 1;
        }

        int k = p.size();
        vector<int> ans;

        for (int i = 0; i < s.size(); ++i) {
            window[s[i] - 'a'] += 1;

            if (i >= k) {
                window[s[i - k] - 'a'] -= 1;
            }

            if (window == need) {
                ans.push_back(i - k + 1);
            }
        }

        return ans;
    }
};