C++: white belt

// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx")

#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <unordered_map>
#include <set>
#include <map>
#include <queue>
#include <random>
#include <chrono>
#include <cassert>
#include <sstream>
#include <fstream>
#include <iomanip>

#define fi first
#define se second
#define pb push_back
#define ll long long
#define ld long double
#define hm unordered_map
#define pii pair<int, int>
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define cinv(v) for (auto& x: v) cin >> x
#define fr(i, n) for (int i = 0; i < n; ++i)
#define fl(i, l, n) for (int i = l; i < n; ++i)

// #define int ll

template <typename T1, typename T2> inline bool chkmin(T1 &x, const T2 &y) {if (x > y) {x = y; return 1;} return 0;}
template <typename T1, typename T2> inline bool chkmax(T1 &x, const T2 &y) {if (x < y) {x = y; return 1;} return 0;}

using namespace std;

#ifdef LOCAL
    #define dbg(x) cerr << #x << " : " << x << '\n'
#else
    #define dbg(x)
#endif

//tg: @runningcherry

template <typename T1, typename T2> ostream& operator << (ostream& out, const pair<T1, T2>& v) {
    out << v.fi << ", " << v.se;
    return out;
}

template<typename T> ostream& operator << (ostream& out, const vector<T>& v) {
    for (auto& x: v) out << x << " ";
    return out;
}

template <typename T1, typename T2> ostream& operator << (ostream& out, const map<T1, T2>& v) {
    for (auto& x: v) out << x << '\n';
    return out;
}

template<typename T> ostream& operator << (ostream& out, const set<T>& v) {
    for (auto& x: v) out << x << " ";
    return out;
}

template<typename T> ostream& operator << (ostream& out, const multiset<T>& v) {
    for (auto& x: v) out << x << " ";
    return out;
}

template <typename T1, typename T2> istream& operator >> (istream& in, pair<T1, T2>& a) {
    in >> a.fi >> a.se;
    return in;
}

const ll inf = (ll) 2e9;
const ld pi = asin (1) * 2;
const ld eps = 1e-8;
const ll mod = (ll)1e9 + 7;
const ll ns = 97;

const int maxn = 2e5 + 20;

mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());

struct Date {
    int year, month, day;

    inline bool operator < (const Date& other) const {
        if (year == other.year) {
            if (month == other.month) {
                return day < other.day;
            }
            return month < other.month;
        }
        return year < other.year;
    }
};

ostream& operator<< (ostream& out, const Date& date) {
    out << setw (4) << setfill ('0') << date.year << '-' <<
    setw (2) << setfill ('0') << date.month << '-' <<
    setw (2) << setfill ('0') << date.day;
    return out;
}

map <Date, set<string>> kek;

void check_next_char (istream& stream, const string& date) {
    if (stream.peek () != '-') {
        throw runtime_error ("Wrong date format: " + date);
    }
    stream.ignore (1);
}

Date get_date (istream& stream) {
    string date;
    stream >> date;
    if (!stream) throw runtime_error ("Wrong date format: " + date);
    stringstream in (date);
    int year, month, day;
    in >> year;
    check_next_char (in, date);
    in >> month;
    check_next_char (in, date);
    in >> day;
    if (!in) throw runtime_error ("Wrong date format: " + date);
    char x;
    in >> x;
    if (in) throw runtime_error ("Wrong date format: " + date);
    if (month < 1 || 12 < month) throw runtime_error ("Month value is invalid: " + to_string (month));
    if (day < 1 || 31 < day) throw runtime_error ("Day value is invalid: " + to_string (day));
    return {year, month, day};
}

void read () {
    string line;
    if (!getline (cin, line)) exit (0);
    if (line.empty ()) return;
    stringstream stream (line);
    string command;
    stream >> command;
    if (command == "Add") {
        auto date = get_date (stream);
        string event;
        stream >> event;
        kek[date].insert (event);
    } else if (command == "Del") {
        auto date = get_date (stream);
        string event;
        stream >> event;
        if (!stream) {
            int n = sz (kek[date]);
            cout << "Deleted " << n << " events\n";
            kek.erase (date);
        } else {
            if (kek[date].count (event)) {
                cout << "Deleted successfully\n";
            } else {
                cout << "Event not found\n";
            }
            kek[date].erase (event);
        }
    } else if (command == "Find") {
        auto date = get_date (stream);
        for (const auto& s: kek[date]) cout << s << '\n';
    } else if (command == "Print") {
        for (const auto& ptt: kek) {
            for (const auto& s: ptt.se) {
                cout << ptt.fi << ' ' << s << '\n';
            }
        }
    } else {
        throw runtime_error ("Unknown command: " + command);
    }
}

signed main () {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    while (1) {
        try {
            read ();
        } catch (exception& ex) {
            cout << ex.what () << '\n';
        }
    }






}