Submission #1221740

#	Time	Username	Problem	Language	Result	Execution time	Memory
1221740		The_Samurai	Making Friends on Joitter is Fun (JOI20_joitter2)	C++20	100 / 100	512 ms	70444 KiB

joitter2

// I stand with PALESTINE



//#pragma GCC optimize("Ofast")
//#pragma GCC optimize ("unroll-loops")
//#pragma GCC target("avx,avx2")

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
//using namespace __gnu_pbds;

#define int long long
#define ff first
#define ss second
#define sz(a) (int) (a).size()
//template<class T, class C = null_type> using ordered_tree = tree<T, C, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long double ld;

namespace io {

    template<typename F, typename S>
    ostream &operator<<(ostream &os, const pair<F, S> &p) { return os << p.ff << " " << p.ss; }

    template<typename F, typename S>
    ostream &operator<<(ostream &os, const map<F, S> &mp) {
        for (auto it: mp) { os << it << endl; }
        return os;
    }

    template<typename F>
    ostream &operator<<(ostream &os, const vector<F> &v) {
        bool space = false;
        for (F x: v) {
            if (space) os << " ";
            space = true;
            os << x;
        }
        return os;
    }

    template<typename F>
    ostream &operator<<(ostream &os, const deque<F> &d) {
        bool space = false;
        for (F x: d) {
            if (space) os << " ";
            space = true;
            os << x;
        }
        return os;
    }

    template<typename F>
    ostream &operator<<(ostream &os, const set<F> &st) {
        bool space = false;
        for (F x: st) {
            if (space) os << " ";
            space = true;
            os << x;
        }
        return os;
    }

    template<typename F>
    ostream &operator<<(ostream &os, const multiset<F> &st) {
        bool space = false;
        for (F x: st) {
            if (space) os << " ";
            space = true;
            os << x << x;
        }
        return os;
    }

    template<typename F, typename S>
    istream &operator>>(istream &is, pair<F, S> &p) { return is >> p.ff >> p.ss; }

    template<typename F>
    istream &operator>>(istream &is, vector<F> &v) {
        for (F &x: v) { is >> x; }
        return is;
    }

    long long fastread() {
        char c;
        long long d = 1, x = 0;
        do c = getchar(); while (c == ' ' || c == '\n');
        if (c == '-') c = getchar(), d = -1;
        while (isdigit(c)) {
            x = x * 10 + c - '0';
            c = getchar();
        }
        return d * x;
    }

    static bool sep = false;

    using std::to_string;

    string to_string(bool x) {
        return (x ? "true" : "false");
    }

    string to_string(const string &s) { return "\"" + s + "\""; }

    string to_string(const char *s) { return "\"" + string(s) + "\""; }

    string to_string(const char &c) {
        string s;
        s += c;
        return "\'" + s + "\'";
    }

    template<typename Type>
    string to_string(vector<Type>);

    template<typename F, typename S>
    string to_string(pair<F, S>);

    template<typename Collection>
    string to_string(Collection);

    template<typename F, typename S>
    string to_string(pair<F, S> p) { return "{" + to_string(p.ff) + ", " + to_string(p.ss) + "}"; }

    template<typename Type>
    string to_string(vector<Type> v) {
        bool sep = false;
        string s = "[";
        for (Type x: v) {
            if (sep) s += ", ";
            sep = true;
            s += to_string(x);
        }
        s += "]";
        return s;
    }

    template<typename Collection>
    string to_string(Collection collection) {
        bool sep = false;
        string s = "{";
        for (auto x: collection) {
            if (sep) s += ", ";
            sep = true;
            s += to_string(x);
        }
        s += "}";
        return s;
    }

    void print() {
        cout << endl;
        sep = false;
    }

    template<typename F, typename... Other>
    void print(F ff, Other... other) {
        if (sep) cout << " | ";
        sep = true;
        cout << to_string(ff);
        print(other...);
    }

}
using namespace io;

namespace utils {

    template<typename F, typename S>
    inline void maxs(F &a, S b) { a = a > b ? a : b; }

    template<typename F, typename S>
    inline void mins(F &a, S b) { a = a < b ? a : b; }

    template<typename F, typename S>
    long long max(F a, S b) { return a > b ? a : b; }

    template<typename F, typename S>
    long long min(F a, S b) { return a < b ? a : b; }

    constexpr long long operator "" _E(unsigned long long n) {
        long long p = 1, a = 10;
        for (int i = 0; i < n; i++) p *= a;
        return p;
    }

    random_device rd;
    mt19937 mt(rd());

    template<typename T>
    T rand(T l, T r) {
        uniform_int_distribution<T> dist(l, r);
        return dist(mt);
    };

}
using namespace utils;


#ifdef sunnatov
#define print(...) cout << "[" << #__VA_ARGS__ << "]: "; io::print( __VA_ARGS__ );
#else
#define print( ... ) 42
#endif

const int mod = 9_E + 7;
const double EPS = 1e-7;
long long doxuya = 18_E + 10;
int INF = 9_E + 10;
const char nl = '\n';

int month[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

/*

*/

void solution(istream &cin, ostream &cout, const int &test_case) {
    int n, m;
    cin >> n >> m;
    // vector con(n + 1, vector(n + 1, false));
    // auto brute = [&](int u, int v) -> int {
    //     con[u][v] = true;
    //     for (int t = 0; t < n; t++) {
    //         for (int i = 1; i <= n; i++) for (int j = 1; j <= n; j++) for (int k = 1; k <= n; k++) {
    //             if (i == j or i == k or j == k) continue;
    //             if (con[i][j] and con[j][k] and con[k][j]) con[i][k] = true;
    //         }
    //     }
    //     int ans = 0;
    //     for (int i = 1; i <= n; i++) for (int j = 1; j <= n; j++) ans += con[i][j];
    //     return ans;
    // };

    vector<vector<int>> have(n + 1);
    vector<set<pair<int, int>>> in(n + 1);
    vector<set<int>> out(n + 1), all_out(n + 1);
    vector<int> par(n + 1), size(n + 1, 1);
    int ans = 0;
    for (int i = 1; i <= n; i++) par[i] = i;
    for (int i = 1; i <= n; i++) have[i].emplace_back(i);

    auto check = [&](set<pair<int, int>> &st, int u) -> bool {
        auto it = st.lower_bound(make_pair(u, 0));
        return it != st.end() and it->first == u;
    };

    queue<pair<int, int>> q;
    auto merge = [&](int u, int v) -> void {
        u = par[u]; v = par[v];
        if (size[u] + sz(in[u]) + sz(all_out[u]) < size[v] + sz(in[v]) + sz(all_out[v])) swap(u, v);
        ans -= size[u] * (size[u] - 1);
        ans -= size[v] * (size[v] - 1);
        ans -= sz(in[u]) * size[u];
        ans -= sz(in[v]) * size[v];

        size[u] += size[v];
        for (int x: have[v]) {
            have[u].emplace_back(x);
            par[x] = u;
            for (int y: out[x]) {
                in[y].erase(make_pair(v, x));
                if (y == u) continue;
                in[y].emplace(u, x);
                all_out[u].insert(y);
                if (check(in[u], y)) q.emplace(u, y);
            }
        }
        for (auto [x, y]: in[v]) {
            if (x == u) {
                out[y].erase(v);
                if (all_out[x].count(v)) all_out[x].erase(v);
                continue;
            }
            out[y].erase(v); out[y].insert(u);
            if (all_out[x].count(v)) all_out[x].erase(v);
            all_out[x].insert(u);
            in[u].emplace(x, y);
            if (all_out[u].count(x)) q.emplace(u, x);
        }
        have[v].clear(); in[v].clear(); all_out[v].clear();

        ans += size[u] * (size[u] - 1);
        ans += sz(in[u]) * size[u];
    };

    while (m--) {
        int u, v;
        cin >> u >> v;
        if (par[u] == par[v]) {
            // assert(ans == brute(u, v));
            cout << ans << nl;
            continue;
        }
        if (!check(in[par[u]], par[v])) {
            if (!out[u].count(par[v])) {
                out[u].insert(par[v]);
                all_out[par[u]].insert(par[v]);
                in[par[v]].emplace(par[u], u);
                ans += size[par[v]];
            }
            // assert(ans == brute(u, v));
            cout << ans << nl;
            continue;
        }
        q.emplace(u, v);
        while (!q.empty()) {
            auto [u, v] = q.front(); q.pop();
            if (par[u] != par[v]) merge(u, v);
        }
        // print(ans);
        // print(brute(u, v));
        // assert(ans == brute(u, v));
        cout << ans << nl;
    }
}

int32_t main() {
    clock_t startTime = clock();
    cin.tie(0)->sync_with_stdio(false);
    srand(time(0));

    std::istream &in(std::cin);
    std::ostream &out(std::cout);

    int32_t queries = 1;

#ifdef test_cases
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    cin >> queries;
#else
    // cin >> queries;
#endif

    for (int32_t test_case = 1; test_case <= queries; test_case++) {
        print(test_case);
        solution(cin, cout, test_case);
        cout << nl;
    }

#ifdef sunnatov
    cout << "Time: " << (int) ((double) (clock() - startTime) / CLOCKS_PER_SEC * 1000) << " ms" << endl;
#endif

    return EXIT_SUCCESS;
}

• Subtask 1: 1 / 1
• Subtask 2: 16 / 16
• Subtask 3: 83 / 83