Submission #926702

#	Time	Username	Problem	Language	Result	Execution time	Memory
926702		Wansur	Cyberland (APIO23_cyberland)	C++17	13 / 100	558 ms	64092 KiB

cyberland

#include <bits/stdc++.h>
#define f first
#define s second
#define ent '\n'
 
using namespace std;
typedef long long ll;
const int mx=1e5+12;
 
vector<pair<int,int>> g[mx];
double d[mx][101];
bool was[mx][101];
bool used[mx];
 
void dfs(int v){
	used[v]=1;
	for(auto to:g[v]){
		if(!used[to.f]){
			dfs(to.f);
		}
	}
}
 
double solve(int n, int m, int k, int h, vector<int> x, vector<int> y, vector<int> c, vector<int> arr){
	k=min(k,70);
	for(int i=0;i<n;i++){
		g[i].clear();
		used[i]=0;
	}
	for(int i=0;i<m;i++){
		g[x[i]].push_back({y[i],c[i]});
		g[y[i]].push_back({x[i],c[i]});
	}
	dfs(0);
	if(!used[h]){
		return -1;
	}
	for(int i=0;i<n;i++){
		for(int x=0;x<=k;x++){
			d[i][x]=-2e14;
			was[i][x]=0;
		}
		used[i]=0;
	}
	used[h]=1;
	dfs(0);
	priority_queue<pair<double,pair<int,int>>> s;
	d[0][0]=0;
	s.push({0,{0,0}});
	for(int i=0;i<n;i++){
		if(used[i] && arr[i]==0){
			d[i][0]=0;
			s.push({0,{i,0}});
		}
	}
	while(s.size()){
		int v=s.top().s.f,x=s.top().s.s;
		s.pop();
		if(v==h)continue;
		if(was[v][x])continue;
		was[v][x]=1;
		for(auto To:g[v]){
			int to=To.f, w=To.s;
			if(d[to][x]<d[v][x]-w){
				d[to][x]=d[v][x]-w;
				s.push({-d[to][x],{to,x}});
			}
			if(x<k && d[to][x+1]<d[v][x]/(long double)2.0-w && arr[v]==2){
				d[to][x+1]=d[v][x]/(long double)2.0-w;
				s.push({-d[to][x+1],{to,x+1}});
			}
		}
	}
	double ans=2e14;
	for(int x=k;x>=0;x--){
		d[h][x]*=-1;
		if(d[h][x]>=2e14)continue;
		ans=min(ans,d[h][x]);
		if(arr[h]==2 && x>0 && d[h][x-1]<2e14)ans=min(ans,d[h][x-1]/(double)2.0);
	}
	return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 0 / 13
• Subtask 4: 0 / 19
• Subtask 5: 0 / 7
• Subtask 6: 0 / 16
• Subtask 7: 0 / 29
• Subtask 8: 0 / 3