LeetCode 438. 找到字符串中所有字母异位词 中等

我的解题

#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
    vector<int> findAnagrams(string s, string p)
    {

        unordered_map<char, int> need, window;
        for (auto &&c : p)
        {
            ++need[c];
        }
        int str_len = s.size();
        int p_len = p.size();
        int left = 0, right = 0;
        int valid = 0; //window中，有效字符的个数
        int start = 0;
        vector<int> res;
        while (right < str_len)
        {
            char c = s[right]; // 新进入的字符
            ++right;
            if (need.count(c))
            {
                ++window[c];
                if (window[c] == need[c])
                {
                    ++valid;
                }
            }
            while (right - left >= p_len) //
            {
                if (valid == need.size())
                {
                    res.push_back(left);
                }
                char d = s[left];
                ++left;
                if (window[d] > 0) // c是目标字符
                {
                    if (window[d] == need[d])
                    {
                        --valid;
                    }
                    --window[d];
                }
            }
        }
        return res;
    }
};
int main()
{
    std::string s { "cbaebabacd" };
    std::string p { "abc" };
    Solution solu;
    auto res = solu.findAnagrams(s, p);
    for (auto &&v : res)
    {
        cout << v << endl;
    }
}
// g++ test.cpp --std=c++11 -pedantic -Wall -Wextra -g