Submission #424082

#	Time	Username	Problem	Language	Result	Execution time	Memory
424082		Supersonic	Stations (IOI20_stations)	C++14	100 / 100	1061 ms	884 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
vector<int> g[1005];int l[1005];int z[1005];
int w(int n,int a){
	int c=1;
	for(auto i:g[n])if(i!=a)c+=w(i,n);
	z[n]=c;return c;
}
void d(int n,int a,int e,bool p){
	if(p)l[n]=a+z[n];
	else l[n]=a-z[n];
	int f=l[n];//cerr<<n<<' '<<f<<endl;
	for(auto i:g[n])if(i!=e){d(i,f,n,!p);f=l[i];}
}
std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
	for(int i=0;i<n-1;i++){g[u[i]].push_back(v[i]);g[v[i]].push_back(u[i]);}
	w(0,n);d(0,n,n,0);vector<int> r;
	for(int i=0;i<n;i++){r.push_back(l[i]);g[i].clear();}
	return r;
}

int find_next_station(int s, int t, std::vector<int> c) {
	if(s<c[0]){
		if(t<s||t>=c.back())return c.back();
		for(auto i:c)if(t<=i)return i;
	}
	else{
		reverse(c.begin(),c.end());
		if(t>s||t<=c.back())return c.back();
		for(auto i:c)if(t>=i)return i;
	}
	exit(1);
}

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 16 / 16
• Subtask 4: 10 / 10
• Subtask 5: 61 / 61