Submission #1313218

#	Time	Username	Problem	Language	Result	Execution time	Memory
1313218		BigBadBully	기지국 (IOI20_stations)	C++20	Compilation error	0 ms	0 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>
#define pii pair<int,int>
#define ff first
#define ss second
using namespace std;
const int inf = 1e9;


vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
	vector<int> bi(n,0);
	vector<int> sbt(n,1),c(n,1);
	vector<vector<int>> graph(n);
	for(int i = 0; i < n-1; i++)
	{
		graph[u[i]].push_back(v[i]);
		graph[v[i]].push_back(u[i]);
	}
	function<void(int,int)> dfs = [&](int cur,int prev)
	{
		c[cur] = 1-c[prev];
		for(int a : graph[cur])
			if(a!=prev)
				dfs(a,cur),sbt[cur]+=sbt[a];
	};
	dfs(0,0);
	int t = 0;
	dfs =[&](int cur,int prev)
	{
		if(c[cur])
			bi[cur]=t+sbt[cur]-1;
		else
			bi[cur]=t++;
		for(int a : graph[cur])
			if(a!=prev)
				dfs(a,cur);
		if(c[cur])t++;
	};
	dfs(0,0);
	return bi;
}

int find_next_station(int s, int t, vector<int> c) {
	if(find(c.begin(),c.end(),t)!=c.end())
		return t;
	if(s==0)
		return *upper_bound(c.begin(),c.end(),t);
	if(s < c[0])
	{
		c.insert(c.begin(),s);
		if(t<c[0])
			return c.back();
		if(t>c.back())
			return c.back();
		int x = *upper_bound(c.begin(),c.end(),t);	
		return x;
	}
	else
	{
		c.push_back(s);
		if(t<c[0])
			return c[0];
		if(t>c.back())
			return c[0];
		int x = *--upper_bound(c.begin(),c.end(),t);
		return x;
	}
	return c[0];
}


static int max_label = 0;
static int r, n, k, q;
static std::vector<int> u, v, labels, answers;
static std::map<int, int> reverse_labels;
static std::vector<std::vector<int>> adjlist;
static int s, t, w;
static std::vector<int> c;

int main() {
	assert(scanf("%d", &r) == 1);
	//srand(time(0));
	cin >> n >> k >> q;
	for (int tc = 0; tc < r; tc++) {
		
		u.resize(n - 1);
		v.resize(n - 1);
		for(int i = 0; i < n; i++)
			v[i] = i+1;
		for(int i = 0; i < n; i++)
			u[i] = i;
		adjlist.clear();
		adjlist.resize(n);
		for (int i = 0; i < n - 1; i++) {
			adjlist[u[i]].push_back(v[i]);
			adjlist[v[i]].push_back(u[i]);
		}
		labels = label(n, k, u, v);

		if ((int)labels.size() != n) {
			printf("Number of labels not equal to %d\n", n);
			exit(0);
		}
		reverse_labels.clear();
		for (int i = 0; i < n; i++) {
			if (labels[i] < 0 || labels[i] > k) {
				printf("Label not in range 0 to %d\n", k);
				exit(0);
			}
			if (reverse_labels.find(labels[i]) != reverse_labels.end()) {
				printf("Labels not unique\n");
				exit(0);
			}
			reverse_labels[labels[i]] = i;
			if (labels[i] > max_label) {
				max_label = labels[i];
			}
		}
		
		for (int i = 0; i < q; i++) {
			int cnt= 0;
			s = rand()%n;
			t = rand()%n;
			while(t==s)
				t = rand()%n;
			c.clear();
			for (int v : adjlist[s]) {
				c.push_back(labels[v]);
			}
			std::sort(c.begin(), c.end());
			int answer = find_next_station(labels[s], labels[t], c);
			if (!std::binary_search(c.begin(), c.end(), answer)) {
				printf("Label %d returned by find_next_station not found in c\n", answer);
				exit(0);
			}
			answers.push_back(reverse_labels[answer]);
		}
	}
	printf("%d\n", max_label);
	for (int index : answers) {
		printf("%d\n", index);
	}
	exit(0);
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccJLKD2p.o: in function `main':
stub.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccie9fu8.o:stations.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status