#849851 (C++17) No.1519 Diversity

• 問題: No.1519 Diversity
• ユーザー: T101010101
• 提出日時: 2023-03-17 17:34:00
• 言語: C++17 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 210 ms / 2,000 ms
• コード長: 8,012 bytes
• コンパイル時間: 4,289 ms
• コンパイル使用メモリ: 306,760 KB
• 実行使用メモリ: 5,484 KB
• 最終ジャッジ日時: 2024-09-18 10:03:47
• 合計ジャッジ時間: 7,039 ms
• ジャッジサーバーID （参考情報）: judge3 / judge4

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	2 ms; 5,248 KB
testcase_01	AC	2 ms; 5,376 KB
testcase_02	AC	2 ms; 5,376 KB
testcase_03	AC	41 ms; 5,376 KB
testcase_04	AC	134 ms; 5,376 KB
testcase_05	AC	2 ms; 5,376 KB
testcase_06	AC	199 ms; 5,376 KB
testcase_07	AC	2 ms; 5,376 KB
testcase_08	AC	9 ms; 5,376 KB
testcase_09	AC	44 ms; 5,376 KB
testcase_10	AC	97 ms; 5,376 KB
testcase_11	AC	2 ms; 5,376 KB
testcase_12	AC	176 ms; 5,416 KB
testcase_13	AC	210 ms; 5,484 KB
testcase_14	AC	205 ms; 5,376 KB
testcase_15	AC	196 ms; 5,376 KB

ソースコード

#pragma region Macros

#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

#include <bits/extc++.h>
using namespace std;
using namespace __gnu_pbds;
// using namespace __gnu_cxx;

// #include <boost/multiprecision/cpp_int.hpp>
// namespace mp = boost::multiprecision;
// using Bint = mp::cpp_int;

#define TO_STRING(var) # var
#define pb emplace_back
#define ture true
#define int ll
#define endl '\n'

using ll = long long;
using ld = long double;
const ld PI = acos(-1);
const ld EPS = 1e-10;
const int INF = 1 << 30;
const ll INFL = 1LL << 61;
// const int MOD = 998244353;
const int MOD = 1000000007;

__attribute__((constructor))
void constructor() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    // ifstream in("input.txt");
    // cin.rdbuf(in.rdbuf());
    cout << fixed << setprecision(15);
}

class UnionFind {
public:

	UnionFind() = default;

    UnionFind(int n) : par(n), 
	    sz(n, 1) { iota(par.begin(), par.end(), 0); }

	int root(int x) {
		if (par[x] == x) return x;
		return (par[x] = root(par[x]));
	}

	bool unite(int x, int y) {
		int rx = root(x);
		int ry = root(y);

        if (rx == ry) return false;
		if (sz[rx] < sz[ry]) swap(rx, ry);

		sz[rx] += sz[ry];
		par[ry] = rx;

        return true;
	}

	bool issame(int x, int y) {
		return (root(x) == root(y));
	}

	int size(int x) {
		return sz[root(x)];
	}

    int get_sum(int x) {
        return sum[root(x)];
    }

    vector<vector<int>> groups(int n) {
        vector<vector<int>> G(n);
        for (int x = 0; x < n; x++) {
            G[root(x)].push_back(x);
        }
		G.erase(
            remove_if(G.begin(), G.end(),
                [&](const vector<int>& v) { return v.empty(); }),
                    G.end());
        return G;
    }

private:
	vector<int> par;
	vector<int> sz;
    vector<int> sum;
};

template<int mod> class modint{
public:
    int val = 0;
    modint(int x = 0) { while (x < 0) x += mod; val = x % mod; }
    modint(const modint &r) { val = r.val; }

    modint operator -() { return modint(-val); }
    modint operator +(const modint &r) { return modint(*this) += r; }
    modint operator +(const int &q) { modint r(q); return modint(*this) += r; }
    modint operator -(const modint &r) { return modint(*this) -= r; }
    modint operator -(const int &q) { modint r(q); return modint(*this) -= r; }
    modint operator *(const modint &r) { return modint(*this) *= r; }
    modint operator *(const int &q) { modint r(q); return modint(*this) *= r; }
    modint operator /(const modint &r) { return modint(*this) /= r; }
    modint operator /(const int &q) { modint r(q); return modint(*this) /= r; }
    modint& operator ++() { val = (val + 1) % mod; return *this; }
    modint& operator --() { val = (val - 1 + mod) % mod; return *this; }

    modint &operator +=(const modint &r) {
        val += r.val; if (val >= mod) val -= mod;
        return *this;
    }
    modint &operator +=(const int &q) {
        modint r(q); val += r.val; if (val >= mod) val -= mod;
        return *this;
    }
    modint &operator -=(const modint &r) {
        if (val < r.val) val += mod; val -= r.val;
        return *this;
    }
    modint &operator -=(const int &q) {
        modint r(q);  if (val < r.val) val += mod; val -= r.val;
        return *this;
    }
    modint &operator *=(const modint &r) {
        val = val * r.val % mod;
        return *this;
    }
    modint &operator *=(const int &q) {
        modint r(q); val = val * r.val % mod;
        return *this;
    }
    modint &operator /=(const modint &r) {
        int a = r.val, b = mod, u = 1, v = 0;
        while (b) {int t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v);}
        val = val * u % mod; if (val < 0) val += mod;
        return *this;
    }
    modint &operator /=(const int &q) {
        modint r(q); int a = r.val, b = mod, u = 1, v = 0;
        while (b) {int t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v);}
        val = val * u % mod; if (val < 0) val += mod;
        return *this;
    }

    bool operator ==(const modint& r) { return this -> val == r.val; }
    bool operator <(const modint& r) { return this -> val < r.val; }
    bool operator !=(const modint& r) { return this -> val != r.val; }
};

using mint = modint<MOD>;

istream &operator >>(istream &is, mint& x) {
    int t; is >> t;
    x = t;
    return (is);
}
ostream &operator <<(ostream &os, const mint& x) {
    return os << x.val;
}

mint modpow(const mint &a, int n) {
    if (n == 0) return 1;
    mint t = modpow(a, n / 2);
    t = t * t;
    if (n & 1) t = t * a;
    return t;
}

int modpow(int x, int n, int mod) {
    int ret = 1;
    while (n > 0) {
        if (n % 2 == 1) ret = ret * x % mod;
        x = x * x % mod;
        n /= 2;
    }
    return ret;
}

int POW(int x, int y) {
    if (y < 0 or x != 0 && x != 1 && y > 64) {cout << "Error" << endl;return 0;}
    if (y == 0) return 1;
    if (y % 2 == 0) return POW(x * x, y / 2);
    return x * POW(x, y - 1);
}
int ceil(int x, int y) { return (x > 0 ? (x + y - 1) / y : x / y); }

vector<mint> fac, finv, Inv;
void COMinit(int N) {
    fac.resize(N + 1);
    finv.resize(N + 1);
    Inv.resize(N + 1);
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    Inv[1] = 1;
    for (int i = 2; i <= N; i++) {
        fac[i] = fac[i-1] * mint(i);
        Inv[i] = -Inv[MOD % i] * mint(MOD / i);
        finv[i] = finv[i - 1] * Inv[i];
    }
}

mint COM(int N,int K){
    if(N < K)return 0;
    if(N < 0 || K < 0) return 0;
    return fac[N] * finv[K] * finv[N - K];
}

#pragma endregion

bool given_degree_simple_graph(const vector<int>& degree, vector<vector<int>>& G){
    const int N = (int)degree.size();
    const int max_degree = *max_element(degree.begin(), degree.end());
    if (max_degree > N - 1) return false;
    if (accumulate(degree.begin(), degree.end(), 0LL) % 2 == 1) return false;
    G.resize(N);

    vector<stack<int>> bucket(max_degree + 1);
    vector<int> deg_cnt(max_degree + 1, 0);
    for (int i = 0; i < N; i++) bucket[degree[i]].push(i);
    vector<pair<int, int> > deg_seq;
    for (int i = max_degree; i >= 1; --i) {
        deg_cnt[i] = (int)bucket[i].size();
        while (!bucket[i].empty()) {
            deg_seq.emplace_back(i, bucket[i].top()), bucket[i].pop();
        }
    }
    while (!deg_seq.empty()) {
        int pos = 0, rem = deg_seq.back().first, cur_degree;
        const int ver = deg_seq.back().second;
        --deg_cnt[rem], deg_seq.pop_back();
        stack<int> update;
        while (rem > 0) {
            if (pos >= (int)deg_seq.size()) return false;
            cur_degree = deg_seq[pos].first;
            const int start = max(pos, pos + deg_cnt[cur_degree] - rem);
            for (int i = start; i < pos + deg_cnt[cur_degree]; i++) {
                G[ver].push_back(deg_seq[i].second), G[deg_seq[i].second].push_back(ver);
                --deg_seq[i].first, update.push(cur_degree);
            }
            pos += deg_cnt[cur_degree], rem -= deg_cnt[cur_degree];
        }
        while (!update.empty()) {
            --deg_cnt[update.top()], ++deg_cnt[update.top() - 1], update.pop();
        }
        while (!deg_seq.empty() && deg_seq.back().first == 0) deg_seq.pop_back();
    }
    return true;
}

signed main() {
    int N;
    cin >> N;

    int sum = 0;
    vector<int> A(N - 1);
    for (int i = 0; i < N - 1; i++) {
        A[i] = i + 1;
        sum += A[i];
    }

    for (int i = 0; i < N - 1; i++) {
        A.pb(i + 1);
        sum += A.back();

        vector<vector<int>> G;
        if (given_degree_simple_graph(A, G)) {
            cout << sum / 2 << endl;
            for (int i = 0; i < N; i++) {
                int sz = G[i].size();
                for (int j = 0; j < sz; j++) {
                    if (i > G[i][j]) continue;
                    cout << i + 1 << " " << G[i][j] + 1 << endl;
                }
            }
            return 0;
        }
        sum -= A.back();
        A.pop_back();
    }
}