oj.uz

Submission #90164

# Submission time Handle Problem Language Result Execution time Memory
90164 2018-12-20T17:05:18 Z FiloSanza Dreaming (IOI13_dreaming) C++14
0 / 100
 1000 ms 7160 KB 
#pragma GCC optimize("O3")
#include "dreaming.h"
#include <bits/stdc++.h>

const int INF = 2e9;

using namespace std;

struct arco
{
	int to, p;
};
int N;
vector<vector<arco>> g;
vector<int> dist;
vector<pair<int, int>> centers;
vector<int> temp;

int bfs(int node, bool precalcolo){
	vector<int> padre(N, -1);
	queue<int> q;
	dist[node] = 0;
	q.push(node);

	int maxiNode = node;
	int maxi = 0;
	while(!q.empty()){
		auto curr = q.front();
		q.pop();

		if(maxi < dist[curr])
			maxi = dist[curr], maxiNode = curr;

		for(auto i : g[curr]){
			if(dist[i.to] > dist[curr] + i.p){
				padre[i.to] = curr;
				q.push(i.to);
				dist[i.to] = dist[curr] + i.p;
			}
		}
	}

	// for(auto i : padre)cout << i << " ";
		// cout << "\n\n";
	if(precalcolo)
		temp.push_back(maxiNode);
	else{
		int diameter = maxi;
		int center = maxiNode;
		int curr = maxiNode;
		maxi = maxi;
		// cout << curr <<"\n";
		// cout << "\t" << max(diameter-dist[curr], dist[curr]) << " " << maxi << "\n";
		while(padre[curr] != -1){
			//cout << curr << " " << padre[curr] << "\n";
			curr = padre[curr];
			//cout << curr << "\n";
			if(max(diameter-dist[curr], dist[curr]) < maxi){
				//cout << "\t" << max(diameter-dist[curr], dist[curr]) << " " << maxi << "\n";
				maxi = max(diameter-dist[curr], dist[curr]);
				center = curr;
			}
		}

		centers.push_back({maxi, center});
	}

	return *max_element(dist.begin(), dist.end());
}

int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
	::N = N;
    g.resize(N);
    dist.resize(N);
	centers.reserve(N);
	temp.reserve(N);

    for(int i=0; i<M; i++){
    	g[A[i]].push_back({B[i], T[i]});
    	g[B[i]].push_back({A[i], T[i]});
    }

	fill(dist.begin(), dist.end(), INF);
    for(int i=0; i<N; i++) if(dist[i] == INF)
    	bfs(i, true);

	fill(dist.begin(), dist.end(), INF);
    for(auto i : temp)
    	bfs(i, false);

    int ans = 0;
    sort(centers.begin(), centers.end());
    
    for(int i=0; i<centers.size()-1; i++){
    	ans = max(ans, L + centers.back().first + centers[i].first);
    }

	return ans;
}

Compilation message

dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:84:28: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
     for(int i=0; i<N; i++) if(dist[i] == INF)
                            ^~
dreaming.cpp:87:2: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  fill(dist.begin(), dist.end(), INF);
  ^~~~
dreaming.cpp:94:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0; i<centers.size()-1; i++){
                  ~^~~~~~~~~~~~~~~~~

Subtask #1
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 50 ms 7160 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 50 ms 7160 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 50 ms 7160 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 18.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1076 ms 5900 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #5
0 / 12.0

# Verdict Execution time Memory Grader output
1 Incorrect 50 ms 7160 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 50 ms 7160 KB Output isn't correct
2 Halted 0 ms 0 KB -