Submission #600195

#	Time	Username	Problem	Language	Result	Execution time	Memory
600195		Meloric	Race (IOI11_race)	C++14	43 / 100	251 ms	72776 KiB

race

#include "race.h"
#include <bits/stdc++.h>

#define pb push_back
//#define int int64_t
#define pii pair<int, int>
#define X first
#define Y second
#define all(x) (x).begin(),(x).end()
#define lb lower_bound
#define ub upper_bound

using namespace std;

const int inf = 1e9;

void p(auto A){
	for(auto e : A)cout << e << ' ';
	cout << '\n';
}

struct special_set{
	set<pii> S;
	pii delta = {0, 0};
	
	void insert(pii e){
		S.insert({e.X-delta.X, e.Y-delta.Y});
	}
	void update(pii dx){
		delta.X+=dx.X;
		delta.Y+=dx.Y;
	}
	int find(int x){
		x-=delta.X;
		if(S.lb({x, -inf}) == S.end())return inf;
		if(S.lb({x, -inf})->X != x)return inf;
		return S.lb({x, -inf})->Y+delta.Y;
	}
	pii pop(){
		pii ret = *S.begin();
		S.erase(S.begin());
		ret.X+=delta.X;
		ret.Y+=delta.Y;
		return ret;
	}
	int size(){
		return S.size();
	}
	void p(){
		//for(auto [e, f] : S)cout << e+delta.X << ' '<< f+delta.Y << endl;
	}
};

int best_path(int N, int K, int H[][2], int L[])
{
  int n = N;
  int k = K; 
  vector<vector<pii>> g(n, vector<pii>());
  for(int i = 0; i< n-1; i++){
	  int c = H[i][0];
	  int d = H[i][1];
	  int w = L[i];
	  g[c].pb({d, w});
	  g[d].pb({c, w});
  }
  int ret = inf;
  auto dfs = [&](auto&& self, int u, int p)->special_set{
	  //cout << u << endl;
	  special_set S;
	  S.insert({0, 0});
	  for(auto [v, w] : g[u])if(v!=p){
		  special_set O = self(self, v, u);
		  O.update(make_pair(w, 1));
		  
		  if(S.size() < O.size())swap(S, O);
		  if(u == 0)S.p();
		  while(O.size()){
			  pii e = O.pop();
			  //cout << u << ' '<< e.X << ' '<< e.Y << ' ' << endl;
			  ret = min(ret, e.Y+S.find(k-e.X));
			  S.insert(e);
		  }
	  }
	  return S;
  };
  auto S = dfs(dfs, 0, 0);
  while(S.size()){
	  auto e = S.pop();
	  //cout << e.X << ' '<< e.Y << ' ';
  }
  if(ret == inf)return -1;
  return ret;
}
/*
void solve(){
	int N, K, H[100][2], L[100];
	cin >> N >> K;
	for(int i = 0; i< N-1; i++){
		cin >> H[i][0] >> H[i][1] >> L[i];
	}
	cout << best_path(N, K, H, L);
}
signed main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	int t = 1;
	//cin >> t;
	while(t--)solve();
}
*/

Compilation message (stderr)

race.cpp:17:8: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   17 | void p(auto A){
      |        ^~~~
race.cpp: In lambda function:
race.cpp:71:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   71 |    for(auto [v, w] : g[u])if(v!=p){
      |             ^
race.cpp: In function 'int best_path(int, int, int (*)[2], int*)':
race.cpp:88:9: warning: variable 'e' set but not used [-Wunused-but-set-variable]
   88 |    auto e = S.pop();
      |         ^

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 22 / 22
• Subtask 4: 0 / 57