Submission #625526

#	Time	Username	Problem	Language	Result	Execution time	Memory
625526		JustInCase	Stations (IOI20_stations)	C++17	100 / 100	926 ms	796 KiB

stations

#include "stations.h"
#include <vector>
#include <iostream>
#include <algorithm>

#define int32_t int
#define int64_t long long

const int32_t MAX_N = 1000;

struct Vertex {
	int32_t label;
	std::vector< int32_t > v;
};

Vertex g[MAX_N + 5];

void dfs(int32_t u, int32_t &t, int32_t par, int32_t dep) {
	if(dep % 2 == 0) {
		g[u].label = t++;
	}

	for(auto &v : g[u].v) {
		if(v != par) {
			dfs(v, t, u, dep + 1);
		}
	}

	if(dep % 2 != 0) {
		g[u].label = t++;
	}
}

std::vector< int32_t > label(int32_t n, int32_t k, std::vector< int32_t > u, std::vector< int32_t > v) {
	for(int32_t i = 0; i < n; i++) {
		g[i].v.clear();
	}

	for(int32_t i = 0; i < n - 1; i++) {
		g[u[i]].v.push_back(v[i]);
		g[v[i]].v.push_back(u[i]);
	}
	
	int32_t t = 0;
	dfs(0, t, -1, 0);
	
	std::vector< int32_t > labels(n);
	for(int32_t i = 0; i < n; i++) {
		labels[i] = g[i].label;
	}

	return labels;
}

int32_t find_next_station(int32_t s, int32_t t, std::vector< int32_t > c) {
	if(s < c[0]) {
		if(t > c[c.size() - 2]) {
			return c[c.size() - 1];
		}
		if(t < s) {
			return c[c.size() - 1];
		}
		else {
			return *std::lower_bound(c.begin(), c.end(), t);
		}
	}
	else {
		if(t <= c[0]) {
			return c[0];
		}
		else if(t > s) {
			return c[0];
		}
		else {
			return *--std::upper_bound(c.begin(), c.end(), t);
		}
	}
}

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