a.cpp - NEERC Moscow Subregional 2015-16

#include <bits/stdc++.h>
using namespace std;

map<string, vector<string> > mp;

int main() {
    int n; cin >> n;
    string s;
    string ss;
    for(int q = 0 ; q < n ; q++) {
        cin >> s;
        ss = s;
        for(int i = 0 ; i < ss.size() ; i++) {
            if(s[i] >= 'A' && s[i] <= 'Z') s[i] = s[i] - 'A' + 'a';
        }
        string x = "", y = "";
        bool sy = false;
        for(int i = 0; i < s.size() ; i++) {
            if(s[i] == '@') {
                sy = true;
                continue;
            }
            if(!sy) x += s[i];
            else y += s[i];
        }
        if(y == "bmail.com") {
            string new_x = "";
            for(int i = 0 ; i < x.size() ; i++) {
                if(x[i] == '+') break;
                if(x[i] == '.') continue;
                new_x += x[i];
            }
            string z = new_x + "@" + y;
            mp[z].push_back(ss);
        } else {
            mp[s].push_back(ss);
        }
    }
    cout << mp.size() << "\n";
    for(map<string, vector<string> >::iterator it = mp.begin() ; it != mp.end() ; ++it) {
        cout << it->second.size() << " ";
        for(vector<string>::iterator i = it->second.begin() ; i != it->second.end() ; ++i) {
            cout << *i << " ";
        }
        cout << "\n";
    }
}