제출 #1154509

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1154509		Boycl07	Parkovi (COCI22_parkovi)	C++20	110 / 110	774 ms	32364 KiB

Main

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define int ll
#define rep(i, n) for(int i = 1; (i) <= (n); ++i)
#define forn(i, l, r) for(int i = (l); i <= (r); ++i)
#define ford(i, r, l) for(int i = (r); i >= (l); --i)
#define FOR(i, n) for(int i = 0; i < (n); ++i)
#define FORD(i, n) for(int i = ((n) - 1); i >= 0; --i)
#define fi first
#define se second
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define endl "\n"
#define task "note"
#define sz(a) int(a.size())
#define C(x, y) make_pair(x, y)
#define all(a) (a).begin(), (a).end()
#define bit(i, mask) (mask >> i & 1)

template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }

inline int readInt()       {char c;while(c=getchar(),c!='-'&&(c<'0'||c>'9'));bool sign=(c=='-');if(sign)c=getchar();int n=c-'0';while(c=getchar(),c>='0'&&c<='9')n=10*n+c-'0';return(!sign)?n:-n;}
inline ll readLong()       {char c;while(c=getchar(),c!='-'&&(c<'0'||c>'9'));bool sign=(c=='-');if(sign)c=getchar();ll  n=c-'0';while(c=getchar(),c>='0'&&c<='9')n=10*n+c-'0';return(!sign)?n:-n;}
inline string readString() {char c;while(c=getchar(),c==' '||c=='\n'||c=='\t');string s({c});while(c=getchar(),c!=EOF&&c!=' '&&c!='\n'&&c!='\t')s+=c;return s;}


const int N =  2e5 + 33;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int n, k;
int a[N];
vector<pii> g[N];


const ll INF = 1e17;
int lim;
vector<int> ans;
pll dfs(int u, int p = -1, int wpar = 0)
{
    ll dist = INF, reach = 0;
    for(auto &[v, w] : g[u]) if(v != p)
    {
        pll tmp = dfs(v, u, w);
        maximize(reach, tmp.fi);
        minimize(dist, tmp.se);
    }
    if(reach + dist <= lim) return {0, dist + wpar};
    if(p != -1)
    {
        if(reach + wpar > lim)
        {
            ans.pb(u);
            return {0, wpar};
        }
    }
    else
    {
        ans.pb(u);
        return {0, wpar};
    }
    return {reach + wpar, dist + wpar};
}

bool check(ll threshold)
{
    ans.clear();
    lim = threshold;
    dfs(1);
    return sz(ans) <= k;
}
bool mark[N];
void solve()
{
    cin >> n >> k;
//    rep(i, n) cin >> a[i];
    rep(i, n - 1)
    {
        int u, v, w;
        cin >> u >> v >> w;
        g[u].pb({v, w});
        g[v].pb({u, w});
    }
    ll  l = 0, r = 1e15, res = 1e9;
    while(l <= r)
    {
        ll mid = l + r >> 1;
        if(check(mid)) res = mid, r = mid - 1;
        else l = mid + 1;
    }
    cout << res << endl;
    check(res);
    for(int x : ans) mark[x] = 1, --k;
    rep(i, n) if(k && !mark[i]) mark[i] = 1, --k;
    rep(i, n) if(mark[i]) cout << i << " ";
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    int TC = 1;

    if(fopen(task".inp", "r"))
    {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }



    while(TC--)
    {
        solve();
        cout << endl;
    }

    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

Main.cpp: In function 'int main()':
Main.cpp:112:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  112 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:113:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30
• Subtask 4: 60 / 60