Submission #1024821

#	Time	Username	Problem	Language	Result	Execution time	Memory
1024821		HappyCapybara	Stations (IOI20_stations)	C++17	0 / 100	611 ms	696 KiB

stations

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

int cnt;
vector<vector<int>> g;
vector<int> in, out, d;

void dfs(int cur, int dep){
	if (d[cur] != -1) return;
	d[cur] = dep;
	in[cur] = cnt++;
	for (int next : g[cur]) dfs(next, dep+1);
	out[cur] = cnt++;
}

vector<int> label(int n, int k, vector<int> u, vector<int> v){
	g.resize(n);
	for (int i=0; i<n-1; i++){
		g[u[i]].push_back(v[i]);
		g[v[i]].push_back(u[i]);
	}
	in.resize(n); out.resize(n); d.resize(n, -1);
	cnt = 0;
	dfs(0, 0);
	vector<int> l(n);
	for (int i=0; i<n; i++){
		if (d[i] % 2) l[i] = out[i];
		else l[i] = in[i];
	}
	vector<int> w = l;
	sort(w.begin(), w.end());
	unordered_map<int,int> m;
	for (int i=0; i<n; i++) m[w[i]] = i;
	for (int i=0; i<n; i++) l[i] = m[l[i]];
	return l;
}

int find_next_station(int s, int t, vector<int> c){
	if (c.size() == 0) return c[0];
	if (s == 0){
		vector<int> d(c.size());
		for (int i=0; i<c.size(); i++){
			if (i == 0) d[i] = s+1;
			else d[i] = c[i-1]+1;
			if (d[i] <= t && t <= c[i]) return c[i];
		}
	}
	else {
		int x = 2000;
		for (int y : c) x = min(x, y);
		if (s < x){
			vector<int> d(c.size()-1);
			for (int i=0; i<c.size()-1; i++){
				if (i == 0) d[i] = s+1;
				else d[i] = c[i-1]+1;
				if (d[i] <= t && t <= c[i]) return c[i];
			}
			return c.back();
		}
		else {
			vector<int> d(c.size());
			for (int i=c.size()-1; i>=0; i--){
				if (i == c.size()-1) d[i] = s-1;
				else d[i] = c[i+1]-1;
				if (c[i] <= t && t <= d[i]) return c[i];
			}
			return c[0];
		}
	}
}

Compilation message (stderr)

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:43:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |   for (int i=0; i<c.size(); i++){
      |                 ~^~~~~~~~~
stations.cpp:54:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |    for (int i=0; i<c.size()-1; i++){
      |                  ~^~~~~~~~~~~
stations.cpp:64:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |     if (i == c.size()-1) d[i] = s-1;
      |         ~~^~~~~~~~~~~~~
stations.cpp:71:1: warning: control reaches end of non-void function [-Wreturn-type]
   71 | }
      | ^

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