Submission #119568

# Submission time Handle Problem Language Result Execution time Memory
119568 2019-06-21T11:53:46 Z Sorting Highway Tolls (IOI18_highway) C++14
0 / 100
34 ms 6016 KB
#include <bits/stdc++.h>
#include "highway.h"

using namespace std;

const int MAXN = 1e5 + 7;

long long ask(const vector<int> &w);
void answer(int s, int t);

mt19937 mt();

long long n, m;
vector<int> adj[MAXN], idx[MAXN], w;
bool used[MAXN];

long long a, b;
long long sm;

vector<int> bfs(int x){
	queue<int> q;

	for(int i = 0; i < n; i++){
		used[i] = false;
	}

	q.push(x);
	used[x] = true;
	
	vector<int> v;

	while(!q.empty()){
		int u = q.front();
		q.pop();

		v.push_back(u);

		for(int to: adj[u]){
			if(!used[to]){
				used[to] = true;
				q.push(to);
			}
		}
	}

	return v;
}

int away(int x){
	vector<int> v = bfs(x);

	int l = 0, r = (int)v.size() - 1;

	while(l != r){
		int mid = (l + r) >> 1;

		for(int i = 0; i < n; i++){
			w[i] = 0;
		}

		for(int i = 0; i <= mid; i++){
			w[ v[i] ] = 1;
		}

		long long score = ask(w);

		if((score / b) * a == sm){
			r = mid;
		}
		else{
			l = mid + 1;
		}
	}

	return v[l];
}

void find_pair(int N, vector<int> U, vector<int> V, int A, int B){
	n = N;
	m = U.size();

	for(int i = 0; i < m; i++){
		adj[V[i]].push_back(U[i]);
		adj[U[i]].push_back(V[i]);

		idx[V[i]].push_back(i);
		idx[U[i]].push_back(i);
		w.push_back(0);
	}

	sm = ask(w);
	a = A;
	b = B;

	int l = 0, r = m - 1;

	while(l != r){
		int mid = (l + r) / 2;

		for(int i = 0; i < m; i++){
			w[i] = 0; 
		}
		for(int i = mid + 1; i <= r; i++){
			w[i] = 1;
		}

		long long score = ask(w);
		score -= sm;

		if(score){
			l = mid + 1;
		}
		else{
			r = mid;
		}
	}

	int x, y;

	x = away(U[l]);

	y = away(x);

	answer(x, y);
}

/*
9 1 2
4 8
4 2
8 0
2 5
2 7
2 3
0 1
0 6
*/
# Verdict Execution time Memory Grader output
1 Incorrect 7 ms 4904 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 7 ms 5096 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 26 ms 5880 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 7 ms 5028 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 34 ms 6016 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 31 ms 5896 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -