Submission #130551

# Submission time Handle Problem Language Result Execution time Memory
130551 2019-07-15T13:57:04 Z groeneprof Highway Tolls (IOI18_highway) C++14
6 / 100
411 ms 262148 KB
#include "highway.h"
#include <bits/stdc++.h>
#define int long long
using namespace std;

struct edge{
	int id, v;
};

int N, M, A, B;
vector<vector<edge> > graph;

void dfs(int u, int par, int id, int d, int dist, vector<int>& idlist, vector<int>& vlist){
	if(d == dist){
		idlist.push_back(id);
		vlist.push_back(u);
	}
	for(edge e : graph[u]) if(e.v!=par){
		dfs(e.v, u, e.id, d+1, dist, idlist, vlist);
	}
}

int findT(int S, int par, int dist, int id){
	vector<int> idlist, vlist;
	dfs(S, par, id, 0, dist, idlist, vlist);
	int L = 0, R = idlist.size();
	while(L!=R-1){
		//cout<<"L: "<< L<< "R: "<<R;
		int Mi = (L+R)/2;
		vector<signed> w(M, 0);
		for(int i = L; i<Mi; i++){
			w[idlist[i]]=1;
		}
		if(ask(w)==dist*A){
			L = Mi;
		}
		else{
			R = Mi;
		}
	}
	return vlist[L];
}

int findedge(int dist){
	int L = 0, R = M;
	while(L!=R-1){
		int Mi = (L+R)/2;
		vector<signed> w(M, 0);
		for(int i = L; i<Mi; i++){
			w[i]=1;
		}
		if(ask(w)==dist*A){
			L = Mi;
		}
		else{
			R = Mi;
		}
	}
	return L;
}

void dfs2(int u, int par, int id, vector<signed> & w){
	w[id] = 1;
	for(edge e : graph[u]) if(e.v!=par){
		dfs2(e.v, u, e.id, w);
	}
}

void find_pair(signed _N, vector<signed> U, vector<signed> V, signed _A, signed _B) {
	N = _N;
	M = U.size();
	A = _A;
	B = _B;
	graph.resize(N);
	for(int i = 0; i<M; i++){
		graph[U[i]].push_back({i, V[i]});
		graph[V[i]].push_back({i, U[i]});
	}
	vector<signed> w(M, 0);
	int dist = ask(w)/A;
	int ed = findedge(dist);
	//cout<<"edge: "<<U[ed]<<" "<<V[ed]<<endl;
	dfs2(V[ed], U[ed], ed, w);
	int d1 = (ask(w)-dist*A)/(B-A)-1;
	int d2 = dist - d1 - 1;
	//cout<<"d1: "<<d1<<" d2: "<<d2<<endl;
	int S = findT(V[ed], U[ed], d1, ed);
	int T = findT(U[ed], V[ed], d2, ed);
	answer(S,T);
}
# Verdict Execution time Memory Grader output
1 Correct 2 ms 248 KB Output is correct
2 Incorrect 2 ms 324 KB Output is incorrect: {s, t} is wrong.
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 496 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 20 ms 2140 KB Output is correct
2 Correct 36 ms 3884 KB Output is correct
3 Correct 43 ms 6012 KB Output is correct
4 Correct 169 ms 14864 KB Output is correct
5 Correct 164 ms 14904 KB Output is correct
6 Correct 161 ms 16592 KB Output is correct
7 Correct 153 ms 18096 KB Output is correct
8 Correct 162 ms 15820 KB Output is correct
9 Correct 161 ms 16020 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 412 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 411 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 383 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -