Submission #833963

#	Time	Username	Problem	Language	Result	Execution time	Memory
833963		vjudge1	Pastiri (COI20_pastiri)	C++17	100 / 100	418 ms	86708 KiB

pastiri

/*
Templete by norman/KNN-07
Who tf even love CP :sob:
*/

#ifndef LOCAL
#pragma GCC optimize("Ofast,unroll-loops,inline")
// Bitwise pragma fuck
// #pragma GCC target("avx,avx2,bmi")

// Judges with GCC >= 12 only needs Ofast
// #pragma GCC optimize("O3,no-stack-protector,fast-math,unroll-loops,tree-vectorize")
// MLE optimization
// #pragma GCC optimize("conserve-stack")
// Old judges
// #pragma GCC target("sse4.2,popcnt,lzcnt,abm,mmx,fma,bmi,bmi2")
// New judges. Test with assert(__builtin_cpu_supports("avx2"));
// #pragma GCC target("arch=skylake")
// Atcoder
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma")
#endif

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

// Wish you can debug? YesYes
#ifndef LOCAL
#define cerr \
    if (0)   \
    cerr
#endif

// Policy based DS?
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// using namespace __gnu_pbds;

// Who tf deal with overflow
// #define int long long

/*
pbds blog :
https://codeforces.com/blog/entry/11080
https://codeforces.com/blog/entry/13279
*/
// Useful pbds
// template <typename T>
// using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
// template <typename T>
// using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
// typedef trie<string, null_type, trie_string_access_traits<>, pat_trie_tag, trie_prefix_search_node_update> pref_trie;

#define el '\n'
#define mpp make_pair
#define pb push_back
#define ppb pop_back
#define pf push_front
#define emp emplace_back
#define fi first
#define nd second
#define forinc(i, a, b) for (int i = (a); i <= (b); i++)
#define fordec(i, a, b) for (int i = (a); i >= (b); i--)
#define alle(x) (x).begin(), (x).end()
#define ralle(x) (x).rbegin(), (x).rend()
#define mms(a, v) memset(a, v, sizeof(a))
#define lwb(a, v) lower_bound((a).begin(), (a).end(), v)
#define upb(a, v) upper_bound((a).begin(), (a).end(), v)
#define bit(i, a) (((a) >> (i)) & 1)

#define BIT_SET(a, b) ((a) |= (1ULL << (b)))
#define BIT_CLEAR(a, b) ((a) &= ~(1ULL << (b)))
#define BIT_FLIP(a, b) ((a) ^= (1ULL << (b)))
#define BIT_CHECK(a, b) (!!((a) & (1ULL << (b))))
#define BITMASK_SET(x, mask) ((x) |= (mask))
#define BITMASK_CLEAR(x, mask) ((x) &= (~(mask)))
#define BITMASK_FLIP(x, mask) ((x) ^= (mask))
#define BITMASK_CHECK_ALL(x, mask) (!(~(x) & (mask)))
#define BITMASK_CHECK_ANY(x, mask) ((x) & (mask))
#define POPCNT(mask) __builtin_popcount(mask)
#define POPCNTLL(mask) __builtin_popcountll(mask)
#define CTZ(mask) __builtin_ctz(mask)
#define CTZLL(mask) __builtin_ctzll(mask)

typedef long long ll;
typedef unsigned long long ull;
typedef long double ldb;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef map<int, int> mii;
typedef map<ll, ll> mll;
typedef vector<bool> vb;

template <typename T, typename U>
inline void maximize(T &x, U y)
{
    if (y < x)
        x = y;
}
template <typename T, typename U>
inline void minimize(T &x, U y)
{
    if (x < y)
        x = y;
}
inline int add_m(int a, int b, int mod)
{
    int res = a + b;
    return (res >= mod ? res - mod : res);
}
inline int mod_neg(int a, int b, int mod)
{
    int res;
    if (abs(a - b) < mod)
        res = a - b;
    else
        res = (a - b) % mod;
    return (res < 0 ? res + mod : res);
}
inline int mul_wmod(int a, int b, int c)
{
    ll res = (ll)a * b;
    return (res >= c ? res % c : res);
}
inline int mul_wnmod(int a, int b, int c)
{
    ll res = (ll)a * b;
    return ((res % c) + c) % c;
}

// Debugger Utils
template <typename A, typename B>
ostream &operator<<(ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }

template <size_t i, class T>
ostream &print_tuple_utils(ostream &out, const T &tup)
{
    if constexpr (i == tuple_size<T>::value)
        return out << ")";
    else
        return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup);
}
template <class... U>
ostream &operator<<(ostream &out, const tuple<U...> &t)
{
    return print_tuple_utils<0, tuple<U...>>(out, t);
}
#define db(val) "[" #val " = " << (val) << "] "
// End if debugger utils

namespace Hasher
{
    struct custom_hash
    {
        static uint32_t splitmix64(uint32_t x)
        {
            x += 0x9e3779b97f4a7c15;
            x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
            x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
            return x ^ (x >> 31);
        }
        size_t operator()(uint64_t x) const
        {
            static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
            return splitmix64(x + FIXED_RANDOM);
        }
    };
    struct hash_pair
    {
        template <class T1, class T2>
        size_t operator()(const pair<T1, T2> &p) const
        {
            auto hash1 = custom_hash{}(p.first);
            auto hash2 = custom_hash{}(p.second);
            if (hash1 != hash2)
                return hash1 ^ hash2;
            return hash1;
        }
    };
    struct hash_pair_pair
    {
        template <class T1, class T2>
        size_t operator()(const pair<T1, T2> &p) const
        {
            auto hash1 = custom_hash{}(p.first);
            auto hash2 = hash_pair{}(p.second);
            if (hash1 != hash2)
                return hash1 ^ hash2;
            return hash1;
        }
    };
}
using namespace Hasher;

const string taskname = "WHARF";
const bool tc = 0;

const int oo = 1e9, mod = 1e9 + 7;
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
const ll ool = 1e18;
const ldb eps = 1e-6;
const int MAXN = 1e6;

/*
Author: normankr07
Problem:
Submission links:
Editorial links:
Algorithm:
*/
int n, k;
vector<int> adj[MAXN];
bool vis[MAXN];
int dp[MAXN], d[MAXN];
vector<int> ans;

void dfs(int x, int par)
{
    dp[x] = -1;
    if (!d[x])
        vis[x] = 1;
    for (int k : adj[x])
    {
        if (k == par)
            continue;
        dfs(k, x);
        if (vis[k])
            vis[x] = 1;
        dp[x] = max(dp[x], dp[k] - 1);
    }
    if (vis[x] && dp[x] == d[x])
        vis[x] = 0;
    if (vis[x] && d[par] != d[x] + 1)
    {
        ans.push_back(x);
        dp[x] = d[x];
        vis[x] = 0;
    }
}

void solve()
{
    cin >> n >> k;
    int u, v;
    for (int i = 0; i < n - 1; i++)
    {
        cin >> u >> v;
        adj[u].pb(v);
        adj[v].pb(u);
    }

    for (int i = 1; i <= n; i++)
        d[i] = -1;

    queue<int> q;
    while (k--)
    {
        int memay;
        cin >> memay;
        d[memay] = 0;
        q.push(memay);
    }

    while (q.size())
    {
        auto front = q.front();
        for (int k : adj[front])
        {
            if (d[k] == -1)
            {
                d[k] = d[front] + 1;
                q.push(k);
            }
        }
        q.pop();
    }

    dfs(1, 0);

    cout << ans.size() << el;
    for (auto x : ans)
        cout << x << ' ';
}

int32_t main()
{
    if (fopen((taskname + ".inp").c_str(), "r"))
    {
        freopen((taskname + ".inp").c_str(), "r", stdin);
        freopen((taskname + ".out").c_str(), "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int tsc = 1;
    if (tc)
    {
        cin >> tsc;
    }
    while (tsc--)
    {
        solve();
        cout << el;
    }
#ifdef LOCAL
    cerr << "\n"
         << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
#endif
}

Compilation message (stderr)

pastiri.cpp: In function 'int32_t main()':
pastiri.cpp:290:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  290 |         freopen((taskname + ".inp").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pastiri.cpp:291:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  291 |         freopen((taskname + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 18 / 18
• Subtask 3: 23 / 23
• Subtask 4: 51 / 51