結果
| 問題 |
No.3113 The farthest point
|
| コンテスト | |
| ユーザー |
eiya5498513
|
| 提出日時 | 2025-04-20 19:44:12 |
| 言語 | C++23 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 217 ms / 2,000 ms |
| コード長 | 10,152 bytes |
| コンパイル時間 | 3,821 ms |
| コンパイル使用メモリ | 215,756 KB |
| 実行使用メモリ | 28,248 KB |
| 最終ジャッジ日時 | 2025-04-20 19:44:21 |
| 合計ジャッジ時間 | 8,696 ms |
|
ジャッジサーバーID (参考情報) |
judge1 / judge2 |
(要ログイン)
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 33 |
ソースコード
#if 1
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <queue>
#include <stack>
#include <array>
#include <deque>
#include <algorithm>
#include <utility>
#include <cstdint>
#include <functional>
#include <iomanip>
#include <numeric>
#include <assert.h>
#include <bitset>
#include <list>
#include <cmath>
#ifdef _MSC_VER
#pragma warning( push )
#pragma warning( disable : 26450 )
#pragma warning( disable : 26451 )
#pragma warning( disable : 26498 )
#pragma warning( disable : 4459 )
#endif
#include <atcoder/all>
#ifdef _MSC_VER
#pragma warning( pop )
#endif
auto& in = std::cin;
auto& out = std::cout;
#define all_range(C) std::begin(C), std::end(C)
const double PI = 3.141592653589793238462643383279502884197169399375105820974944;
constexpr int32_t MAX_N = 600000;//頂点数
constexpr int32_t MAX_LOGN = 30;//log2頂点数
struct edge{
int to;
int64_t w;
};
std::vector<edge> graph[MAX_N];//木
namespace nLCA
{
int root; // 根ノードの番号
int parent[MAX_LOGN][MAX_N]; // 親を2^k回辿って到達する頂点(根を通り過ぎる場合は-1とする)
int depth[MAX_N]; // 根からの深さ
int64_t dist[MAX_N]; // 根からの遠さ
void dfs(int v, int p, int d, int64_t w) {
parent[0][v] = p;
depth[v] = d;
dist[v] = w;
for (int i = 0; i < graph[v].size(); i++) {
if (graph[v][i].to != p) dfs(graph[v][i].to, v, d + 1, w + graph[v][i].w);
}
}
// 初期化
void init(int V) {
// parent[0]とdepthを初期化する
dfs(root, -1, 0, 0);
// parentを初期化する
for (int k = 0; k + 1 < MAX_LOGN; k++) {
for (int v = 0; v < V; v++) {
if (parent[k][v] < 0) parent[k + 1][v] = -1;
else parent[k + 1][v] = parent[k][parent[k][v]];
}
}
}
// uとvのLCAを求める
int glca(int u, int v) {
// uとvの深さが同じになるまで親を辿る
if (depth[u] > depth[v]) std::swap(u, v);
for (int k = 0; k < MAX_LOGN; k++) {
if ((depth[v] - depth[u]) >> k & 1) {
v = parent[k][v];
}
}
if (u == v) return u;
// 二分探索でLCAを求める
for (int k = MAX_LOGN - 1; k >= 0; k--) {
if (parent[k][u] != parent[k][v]) {
u = parent[k][u];
v = parent[k][v];
}
}
return parent[0][u];
}
std::pair<int64_t, int64_t> dfs2(int v) {
int64_t max1 = 0;
int64_t max2 = 0;
int64_t max_res = 0;
for (int i = 0; i < graph[v].size(); i++) {
if (graph[v][i].to != parent[0][v]) {
auto new_res = dfs2(graph[v][i].to);
max_res = std::max(max_res, new_res.second);
auto new_d = new_res.first + graph[v][i].w;
if (new_d >= max1) {
max2 = max1;
max1 = new_d;
}
else if (new_d >= max2) {
max2 = new_d;
}
}
}
max_res = std::max(max_res, max1 + max2);
return { max1 ,max_res };
}
}
int32_t N;
void input_tree()
{
in >> N;
for (int32_t i = 0; i < N - 1; ++i)
{
int a, b;
int64_t w;
in >> a >> b >> w; --a; --b;
graph[a].push_back({ b, w });
graph[b].push_back({ a, w });
}
}
int main()
{
using std::endl;
in.sync_with_stdio(false);
out.sync_with_stdio(false);
in.tie(nullptr);
out.tie(nullptr);
input_tree();
nLCA::init(0);
auto res = nLCA::dfs2(0);
out << res.second << endl;
return 0;
}
#endif
#if 0
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <queue>
#include <stack>
#include <array>
#include <deque>
#include <algorithm>
#include <utility>
#include <cstdint>
#include <functional>
#include <iomanip>
#include <numeric>
#include <assert.h>
#include <bitset>
#include <list>
#include <cmath>
#ifdef _MSC_VER
#pragma warning( push )
#pragma warning( disable : 26450 )
#pragma warning( disable : 26451 )
#pragma warning( disable : 26498 )
#pragma warning( disable : 4459 )
#endif
#include <atcoder/all>
#ifdef _MSC_VER
#pragma warning( pop )
#endif
auto& in = std::cin;
auto& out = std::cout;
#define all_range(C) std::begin(C), std::end(C)
const double PI = 3.141592653589793238462643383279502884197169399375105820974944;
template<typename Arithmetic, typename Integral>
std::enable_if_t< std::is_unsigned<Integral>::value, Arithmetic>
ipow(Arithmetic bace, Integral n)
{
//繰り返し二条法
auto res = (Arithmetic)(1);
while (n > 0) {
if (n & 1) res *= bace;
bace *= bace;
n >>= 1;
}
return res;
}
constexpr bool is_prime(uint32_t N)
{
if (N <= 1) {
return false;
}
for (size_t i = 2; i * i <= N; ++i)
{
if (N % i == 0) {
return false;
}
}
return true;
}
template <uint64_t MOD> class mint_base;
//mint_base_base型用の累乗関数
template <uint64_t MOD> constexpr mint_base<MOD> m_pow(mint_base<MOD> x, uint64_t n)noexcept;
//mod計算を自動で行う整数テンプレートクラス
template <uint64_t MOD_ = 998244353>
class mint_base
{
public:
static constexpr auto MOD = MOD_;
static_assert(!(MOD <= 2), "MOD cannot be below 2.");
static_assert(MOD <= (0xFFFFFFFFFFFFFFFF / 2), "MOD is too big");//加算してオーバーフローしない
static_assert(MOD <= 0xFFFFFFFF, "MOD is too big");//乗算してオーバーフローしない
constexpr mint_base<MOD> operator+(const mint_base<MOD>& other)const noexcept
{
auto v = *this;
return v += other;
}
constexpr mint_base<MOD> operator-(const mint_base<MOD>& other)const noexcept
{
auto v = *this;
return v -= other;
}
constexpr mint_base<MOD> operator*(const mint_base<MOD>& other)const noexcept
{
auto v = *this;
return v *= other;
}
constexpr auto operator/(const mint_base<MOD>& other)const noexcept
{
auto v = *this;
return v /= other;
}
constexpr mint_base<MOD>& operator+=(const mint_base<MOD>& other) noexcept
{
a += other.a;
if (MOD <= a) { a -= MOD; };
return *this;
}
constexpr mint_base<MOD>& operator-=(const mint_base<MOD>& other) noexcept
{
if (a >= other.a) {
a -= other.a;
}
else {
a = (a + MOD) - other.a;
}
return *this;
}
constexpr mint_base<MOD>& operator*=(const mint_base<MOD>& other) noexcept
{
#if 1
a *= other.a;
a %= MOD;
#else
//MOD <= (MAXUINT64 / 2)条件下
uint64_t b = other.a, v = 0;
while (b > 0) {
if (b & 1) {
v += a;
if (v >= MOD)v -= MOD;
}
a += a;
if (MOD <= a)a -= MOD;
b >>= 1;
}
a = v;
#endif
return *this;
}
constexpr mint_base<MOD>& operator/=(const mint_base<MOD>& other) noexcept
{
return *this *= ~other;
}
constexpr mint_base<MOD> operator+()const noexcept { return *this; }
constexpr mint_base<MOD> operator-()const noexcept
{
return{ MOD - a, mod_value_tag{} };
}
constexpr mint_base<MOD>& operator++() noexcept
{
if (MOD <= ++a) { a = 0; };
return *this;
}
constexpr mint_base<MOD>& operator--() noexcept
{
if (a <= 0) { a = MOD; };
--a;
return *this;
}
constexpr mint_base<MOD> operator++(int) noexcept
{
auto tmp = *this;
++*this;
return tmp;
}
constexpr mint_base<MOD> operator--(int) noexcept
{
auto tmp = *this;
--*this;
return tmp;
}
constexpr mint_base<MOD> operator~()const noexcept
{
return ipow(*this, e_phi - 1);
}
constexpr mint_base<MOD>& operator=(const mint_base<MOD>& other) noexcept
{
a = other.a;
return *this;
}
constexpr explicit operator uint64_t()const noexcept
{
return a;
}
constexpr explicit operator unsigned()const noexcept
{
return (unsigned)a;
}
static constexpr uint64_t getmod() noexcept
{
return MOD;
}
constexpr mint_base(uint64_t a_) noexcept :a(a_% MOD) {}
constexpr mint_base()noexcept : a(0) {}
struct mod_value_tag {};
constexpr mint_base(uint64_t a_, mod_value_tag) :a(a_) {}
private:
static constexpr uint64_t get_e_phi()noexcept {
//オイラー値の導出
uint64_t temp = MOD;
uint64_t m_ = MOD;
for (uint64_t i = 2; i * i <= m_; ++i)
{
if (m_ % i == 0)
{
temp = temp / i * (i - 1);
for (; m_ % i == 0; m_ /= i);
}
}
if (m_ != 1)temp = temp / m_ * (m_ - 1);
return temp;
}
static constexpr uint64_t e_phi = get_e_phi();//オイラー値
uint64_t a;
};
//mint_base型用の累乗関数
template<uint64_t MOD>constexpr mint_base<MOD> m_pow(mint_base<MOD> x, uint64_t n)noexcept
{
mint_base<MOD> res = 1;
while (n > 0)
{
if (n & 1)res *= x;
x *= x;
n >>= 1;
}
return res;
}
//mint_baseの階乗計算
//O(x)時間が必要のため、fact_set関数を推奨する。
template<uint64_t MOD>constexpr mint_base<MOD> fact(mint_base<MOD> x)noexcept
{
mint_base<MOD> res(1);
for (uint64_t i = 1; i <= (uint64_t)x; ++i)
{
res *= i;
}
return res;
}
//mint_baseの階乗計算
//0からxまでの階乗を返す
//O(x)時間が必要
template<uint64_t MOD>std::vector<mint_base<MOD>> fact_set(mint_base<MOD> x = mint_base<MOD>(-1))
{
mint_base<MOD> res(1);
std::vector<mint_base<MOD>> set((uint64_t)(x)+1);
set[0] = 1;
for (uint64_t i = 1; i <= (uint64_t)x; ++i)
{
res *= i;
set[i] = res;
}
return res;
}
//mint_base型のstreamへの出力
template<uint64_t MOD> std::ostream& operator<<(std::ostream& os, mint_base<MOD> i)
{
os << (uint64_t)i;
return os;
}
//mint_base型のstreamからの入力
template<uint64_t MOD> std::istream& operator >> (std::istream& is, mint_base<MOD>& i)
{
uint64_t tmp;
is >> tmp;
i = tmp;
return is;
}
typedef mint_base<> mint;
namespace mint_literal {
constexpr mint operator""_mi(unsigned long long x)noexcept {
return mint(x);
}
}
using namespace mint_literal;
int64_t A[300000];
mint mn[300000];
int main()
{
using std::endl;
in.sync_with_stdio(false);
out.sync_with_stdio(false);
in.tie(nullptr);
out.tie(nullptr);
int64_t N;
mint M;
in >> N >> M;
for (int i = 0; i < N; i++)
{
in >> A[i];
}
std::sort(A, A + N);
mint over = 0;
mn[0] = 1;
for (size_t i = 1; i < 300000; i++) {
mn[i] = mn[i - 1] * M;
}
mint swapsum = 0;
mint sum = 0;
for (int i = N - 1; i >= 0; i--)
{
if (i != N - 1) {
over = mint(N - i - 1) * mint(A[i + 1] - A[i]);
}
sum += (M - A[i]) * mn[N-1];
auto swap = mint(A[i]) * over * mn[N-2];
swap -= swapsum / M * mint(A[i]);
swapsum += swap;
sum += swap;
}
out << sum << endl;
return 0;
}
#endif
eiya5498513