Submission #1081684

#	Time	Username	Problem	Language	Result	Execution time	Memory
1081684		GrindMachine	Stations (IOI20_stations)	C++17	73.36 / 100	677 ms	1016 KiB

stations

#include <bits/stdc++.h>
using namespace std;

typedef long long int ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define pb push_back
#define endl '\n'
#define conts continue
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define sz(a) (int)a.size()

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &x, T y){
	x = min(x,y);
}

template<typename T>
void amax(T &x, T y){
	x = max(x,y);
}

template<typename A,typename B>
string to_string(pair<A,B> p);

string to_string(const string &s){
	return "'"+s+"'";
}

string to_string(const char* s){
	return to_string((string)s);
}

string to_string(bool b){
	return b?"true":"false";
}

template<typename A>
string to_string(A v){
	string res = "{";
	trav(x,v){
		res += to_string(x)+",";
	}
	if(res.back() == ',') res.pop_back();
	res += "}";
	return res;
}

template<typename A,typename B>
string to_string(pair<A,B> p){
	return "("+to_string(p.ff)+","+to_string(p.ss)+")";
}

#define debug(x) cout << "[" << #x << "]: "; cout << to_string(x) << endl

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = 1e9 + 5;
const ll inf2 = (ll)1e18 + 5;

#include "stations.h"

std::vector<int> label(int n, int k, std::vector<int> U, std::vector<int> V) {
	vector<vector<int>> adj(n);
	rep(i,n-1){
		int u = U[i], v = V[i];
		adj[u].pb(v), adj[v].pb(u);
	}

	vector<int> tin(n), tout(n), subsiz(n), depth(n);
	int timer = 0;

	auto dfs1 = [&](int u, int p, auto &&dfs1) -> void{
		tin[u] = timer++;
		subsiz[u] = 1;
		trav(v,adj[u]){
			if(v == p) conts;
			depth[v] = depth[u]+1;
			dfs1(v,u,dfs1);
			subsiz[u] += subsiz[v];
		}
		tout[u] = timer++;
	};

	dfs1(0,-1,dfs1);

	vector<int> ans(n);
	rep(i,n){
		if(depth[i]&1){
			ans[i] = tout[i]*2+1;
		}
		else{
			ans[i] = tin[i]*2;
		}
	}

	return ans;

	// std::vector<int> labels(n);
	// for (int i = 0; i < n; i++) {
	// 	labels[i] = i;
	// }
	// return labels;
}

int find_next_station(int s, int t, std::vector<int> c) {
	int typ = (s&1);
	s >>= 1, t >>= 1;
	int p = -1;

	if(!typ){
		// tin
		if(s){
			p = c.back();
			c.pop_back();
		}

		int pv = s;
		trav(x,c){
			int tin = pv+1, tout = (x>>1);
			if(tin <= t and t <= tout){
				return x;
			}
			pv = tout;
		}

		return p;
	}
	else{
		// tout
		p = c[0];
		c.erase(c.begin());

		reverse(all(c));
		int pv = s;

		trav(x,c){
			int tin = (x>>1), tout = pv-1;
			if(tin <= t and t <= tout){
				return x;
			}
			pv = tin;
		}

		return p;
	}

	assert(0);
	return -1;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 8
• Subtask 3: 16 / 16
• Subtask 4: 10 / 10
• Subtask 5: 47.3618 / 61