Submission #136482

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
136482	2019-07-25T11:06:31 Z	amiratou	Highway Tolls (IOI18_highway)	C++14	6 / 100	379 ms	262148 KB

highway

#include "highway.h"
#include <bits/stdc++.h>
#define ll long long
#define ii pair<int,int>
#define fi first
#define se second
#define pb push_back
using namespace std;
vector<vector<ii> > vec;
vector<int> query;
vector<ii> target;
ll dist,a,b;
void dfs(int node,int high,int p){
	if(high!=-1)target.pb(ii(high,node));
	for(auto child:vec[node])
		if(child.fi!=p)
			dfs(child.fi,child.se,node);
}
void find_pair(int N, vector<int> U, vector<int> V, int A, int B) {
	int M = U.size();
	a=A,b=B;
	vec.resize(N);
	query.resize(M);
	for (int i = 0; i < M; ++i)
	{
		vec[U[i]].pb(ii(V[i],i));
		vec[V[i]].pb(ii(U[i],i));
	}
	int start=0;
	for (int i = 0; i < N; ++i)
	{
		if(vec[i].size()==1){
			start=i;
			break;
		}
	}
	fill(query.begin(),query.end(),0);
	dist=ask(query);
	dfs(start,-1,0);
	//sort(target.begin(),target.end());
	int l=0,r=(int)(target.size())-1;
	int n1=-1,n2=-1,L=0;
	while(l<r){
		int med=(l+r)>>1;
		L=med;
		fill(query.begin(),query.end(),0);
		for (int i = l; i <= med; ++i)
			query[target[i].fi]=1;
		ll check=ask(query);
		if(check==dist)
			l=med+1;
		else if(check==(dist/A)*B){
			r=med;
		}
		else{
			ll nb_edges=(check-dist)/(B-A);
			//cerr<<l<<" "<<r<<" "<<nb_edges<<" "<<med<<"\n";
			n1=(((med-nb_edges)<0)?start:target[med-nb_edges].se);
			n2=target[med+(dist-nb_edges*A)/A].se;
			//cerr<<n1<<" "<<n2<<"\n";
			break;
		}
	}
	if(n1!=-1)
		answer(n1, n2);
	else
		answer((L?target[L-1].se:start),target[L].se);
}

Subtask #1
0 / 5.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	2 ms	328 KB	Output is incorrect: {s, t} is wrong.
2	Halted	0 ms	0 KB	-

Subtask #2
0 / 7.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	2 ms	376 KB	Output is incorrect: {s, t} is wrong.
2	Halted	0 ms	0 KB	-

Subtask #3
6.0 / 6.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	24 ms	1820 KB	Output is correct
2	Correct	36 ms	3252 KB	Output is correct
3	Correct	56 ms	4896 KB	Output is correct
4	Correct	159 ms	13408 KB	Output is correct
5	Correct	151 ms	13444 KB	Output is correct
6	Correct	164 ms	13424 KB	Output is correct
7	Correct	147 ms	13504 KB	Output is correct
8	Correct	153 ms	13432 KB	Output is correct
9	Correct	156 ms	13556 KB	Output is correct