Submission #1240544

#	Time	Username	Problem	Language	Result	Execution time	Memory
1240544		mychecksedad	봉쇄 시간 (IOI23_closing)	C++17	51 / 100	1097 ms	23364 KiB

closing

#include "closing.h"
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define all(x) x.begin(),x.end()
#define vi vector<int>
#define pii pair<int,int>
#define ff first
#define ss second
#define ll long long int
#define cerr if(0) cerr
const int N = 5000;

ll dp[N][N][2], A[N], B[N], C[N]; // 0 - 1
vector<pair<int, ll>> g[N];
bitset<N> in_path;
int sz[N];
bool dfs(int v, int p, int t, vector<int> &T){
  T.pb(v);
  if(v == t){
    return 1;
  }
  for(auto [u, w]: g[v]){
    if(u != p){
      bool ok = dfs(u, v, t, T);
      if(ok) return true;
    }
  }
  T.pop_back();
  return false;
}

void dfs2(int v, int p){
  vi U;
  sz[v] = 1;
  for(auto [u, w]: g[v]){
    if(u != p && !in_path[u]){
      dfs2(u, v);
      sz[v] += sz[u];
      U.pb(u);
    }
  }
  for(int j = 0; j <= sz[v]; ++j) dp[v][j][0] = 1e18;
  dp[v][0][0] = 0;
  
  int cur = 0;
  for(int u: U){
    cur += sz[u];
    for(int w = cur; w >= 1; --w){
      for(int j = 1; j <= sz[u]; ++j){
        if(w - j < 0) break;
        dp[v][w][0] = min(dp[v][w][0], dp[v][w - j][0] + dp[u][j][0]);
      }    
    }
  }

  for(int j = sz[v]; j >= 1; --j) dp[v][j][0] = dp[v][j - 1][0] + A[v];


  for(int j = 0; j <= sz[v] * 2; ++j) dp[v][j][1] = 1e18;
  dp[v][0][1] = 0;
  
  cur = 0;
  for(int u: U){
    cur += sz[u]*2;
    for(int w = cur*2; w >= 1; --w){
      for(int j = 1; j <= sz[u]*2; ++j){
        if(w - j < 0) break;
        dp[v][w][1] = min(dp[v][w][1], dp[v][w - j][1] + dp[u][j][1]);
      } 
      for(int j = 1; j <= sz[u]; ++j){
        if(w - j < 0) break;
        dp[v][w][1] = min(dp[v][w][1], dp[v][w - j][1] + dp[u][j][0]);
      }       
    }
  }

  for(int j = sz[v] * 2; j >= 2; --j) dp[v][j][1] = dp[v][j - 2][1] + B[v] + A[v];
  dp[v][1][1] = 1e18; // impossible case lol
}

int max_score(int n, int X, int Y, long long K, std::vector<int> U, std::vector<int> V, std::vector<int> W)
{
  for(int i = 0; i < n; ++i) g[i].clear();
  in_path = 0;
  for(int i = 0; i < n-1; ++i){
    g[U[i]].pb({V[i], W[i]});
    g[V[i]].pb({U[i], W[i]});
  }
  vector<ll> dist(n, -1);
  dist[X] = 0;
  queue<int> q;
  q.push(X);
  while(!q.empty()){
    int v = q.front(); q.pop();
    for(auto [u, w]: g[v]){
      if(dist[u] == -1){
        dist[u] = dist[v] + w;
        q.push(u);
      }
    }
  }
  vector<ll> dist2(n, -1);
  dist2[Y] = 0;
  q.push(Y);
  while(!q.empty()){
    int v = q.front(); q.pop();
    for(auto [u, w]: g[v]){
      if(dist2[u] == -1){
        dist2[u] = dist2[v] + w;
        q.push(u);
      }
    }
  }
  for(int i = 0; i < n; ++i){
    A[i] = min(dist[i], dist2[i]);
    B[i] = max(dist[i], dist2[i]) - min(dist[i], dist2[i]);
  }
  vi T; 
  dfs(X, X, Y, T);
  for(int x: T) in_path[x] = 1;

  ll sum = 0;
  for(int x: T){
    sum += A[x];
  }

  int ans = 0;  
  ll KK = K;
  for(int j = 0; j < n; ++j) C[j] = A[j];
  
  sort(C, C+n);
  for(int j = 0; j < n; ++j){
    if(KK>= C[j]) KK-=C[j], ++ans;
  }

  for(int x: T){
    K -= A[x];
    A[x] = 0;
  }

  vector<ll> DP(2*n + 5, 1ll*(1e18));

  cerr << ans << " f\n";
  for(int i = 0; i < n; ++i){
    cerr << A[i] << ' ' << B[i] << '\n';
  }
  cerr << '\n';

  DP[0] = 0;
  int cur = 0;
  for(int v: T){
    dfs2(v, v);
    cur += sz[v] * 2;
    for(int j = cur; j >= 0; --j){
      for(int w = 1; w <= 2*sz[v]; ++w){
        if(j - w < 0) break;
        if(w <= sz[v]){
          DP[j] = min(DP[j], DP[j - w] + dp[v][w][0]);
        }
        DP[j] = min(DP[j], DP[j - w] + dp[v][w][1]);
      }
    }
    for(int j = 0; j <= cur; ++j){
      cerr << DP[j] << ' ';
    }
    cerr << '\n';
  }
  cerr << '\n';
  cerr << '\n';
  for(int v = 0; v < n; ++v){

    cerr << v << ' ' << sz[v] << ":\n";
    for(int j = 0; j <= sz[v]; ++j){
      cerr << dp[v][j][0] << ' ';
    }
    cerr << '\n';
  }
  for(int i = 2*n; i >= 0; --i) if(DP[i] <= K) return max(i, ans);
  return ans;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 9 / 9
• Subtask 3: 12 / 12
• Subtask 4: 0 / 14
• Subtask 5: 9 / 9
• Subtask 6: 11 / 11
• Subtask 7: 10 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17