kUSfqhSL

1#include <iostream>
2#include <unordered_map>
3#include <string>
4#include <vector>
5#include <algorithm>
6 
7using namespace std;
8 
9int main() {
10    unordered_map<string, vector <string>> my_map;
11    int n;
12    cin >> n;
13    string str;
14 
15    for (int i = 0; i < n; i++)
16    {
17        cin >> str;
18        string newstring = "";
19        string strorigin = str;
20        transform (str.begin(), str.end(), str.begin(), ::tolower);
21        int pos = str.find('@');
22        if (!str.compare(pos, str.size() - pos, "@gmail.com"))
23        {
24            string empty = "";
25            auto iter1 = str.begin();
26            auto iter2 = str.begin();
27            bool has_plus = false;
28            while (*iter1 != '@') {
29                if (*iter1 == '+') {
30                    has_plus = true;
31                }
32                if (!has_plus) {
33                    if (*iter1 == '.') {
34                        iter1++;
35                    } else {
36                        *iter2 = *iter1;
37                        iter1++;
38                        iter2++;
39                    }
40                } else {
41                    iter1++;
42                }
43            }
44            while (iter1 != str.end()) {
45                *iter2 = *iter1;
46                iter1++;
47                iter2++;
48            }
49            str.replace(iter2, iter1, empty.begin(), empty.end());
50        }
51        if (my_map.find(str) == my_map.end())
52        {
53            my_map[str] = vector<string>();
54        }
55        my_map[str].push_back(strorigin);
56    }
57    cout << my_map.size() << endl;
58    for (const auto &item0 :my_map)
59    {
60        cout << item0.second.size();
61        for (size_t i = 0; i < item0.second.size(); i++)
62        {
63            cout << ' ' << item0.second[i];
64        }
65        cout << endl;
66    }
67    return 0;
68}