Submission #716491

#	Time	Username	Problem	Language	Result	Execution time	Memory
716491		myrcella	Stations (IOI20_stations)	C++17	Compilation error	0 ms	0 KiB

stations

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

#define fi first
#define se second
#define pii pair<int,int>
#define pll pair<long long,long long>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl
#define pq priority_queue
#define inf 0x3f
#define rep(i,a,b) for (int i=a;i<(b);i++)
#define MP make_pair
#define SZ(x) (int(x.size()))
#define ll long long
#define mod 1000000007
#define ALL(x) x.begin(),x.end()
void inc(int &a,int b) {a=(a+b)%mod;}
void dec(int &a,int b) {a=(a-b+mod)%mod;}
int lowbit(int x) {return x&(-x);}
ll p0w(ll base,ll p) {ll ret=1;while(p>0){if (p%2ll==1ll) ret=ret*base%mod;base=base*base%mod;p/=2ll;}return ret;}

//#include "stations.h"

const int maxn = 1010;

vector<int> l;
vector <int> edge[maxn];

int dfs(int u,int pos,int flag,int lst) {
	int ret = pos;
	if (flag==1) l[u] = pos++;
	for (int v:edge[u]) {
		if (v==lst) continue;
		pos += dfs(v,pos,flag^1,u);
	}
	if (flag==0) l[u] = pos++;
//	debug(233),cout<<u<<" "<<l[u]<<endl;
	return pos-ret;
}

std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
	l.resize(n);
	rep(i,0,n-1) {
		edge[u[i]].pb(v[i]);
		edge[v[i]].pb(u[i]);
	}
	dfs(0,0,0,-1);
	return l;
}

int find_next_station(int s, int t, std::vector<int> c) {
	if (c.back()<s) {
		rep(i,1,SZ(c)-1) {
			if (t>=c[i] and t<c[i+1]) return c[i];
		}
		if (t>=c.back() and t<s) return c.back();
		return c[0];
	}
	else {
//		assert(c[0]>s);
		if (t>s and t<=c[0]) return c[0];
		rep(i,1,SZ(c)-1) if (t>c[i-1] and t<=c[i]) return c[i];
		return c.back();
	}
}

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);
	for (int tc = 0; tc < r; tc++) {
		assert(scanf("%d%d", &n, &k) == 2);
		u.resize(n - 1);
		v.resize(n - 1);
		adjlist.clear();
		adjlist.resize(n);
		for (int i = 0; i < n - 1; i++) {
			assert(scanf("%d%d", &u[i], &v[i]) == 2);
			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];
			}
		}
		assert(scanf("%d", &q) == 1);
		for (int i = 0; i < q; i++) {
			assert(scanf("%d%d%d", &s, &t, &w) == 3);
			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/ccCp6xql.o: in function `main':
stub.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccRLDlhp.o:stations.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status