oj.uz

Submission #61258

# Submission time Handle Problem Language Result Execution time Memory
61258 2018-07-25T14:15:39 Z Eae02 Dreaming (IOI13_dreaming) C++14
18 / 100
 70 ms 14328 KB 
#include "dreaming.h"

#include <bits/stdc++.h>

struct Edge
{
	int len;
	struct Node* next;
};

struct Node
{
	std::vector<Edge> edges;
	int diamEdge;
	int component = -1;
};

void initComponent(Node* node)
{
	for (const Edge& e : node->edges)
	{
		if (e.next->component != -1)
			continue;
		e.next->component = node->component;
		initComponent(e.next);
	}
}

std::pair<Node*, int> furthestNode(Node* node, Node* prev)
{
	std::pair<Node*, int> furthest(node, 0);
	for (int i = 0; i < node->edges.size(); i++)
	{
		if (node->edges[i].next == prev)
			continue;
		auto c = furthestNode(node->edges[i].next, node);
		c.second += node->edges[i].len;
		if (c.second > furthest.second)
		{
			node->diamEdge = i;
			furthest = c;
		}
	}
	return furthest;
}

int travelTime(int numNodes, int numEdges, int newEdgeLen, int A[], int B[], int T[])
{
	std::vector<Node> nodes(numNodes);
	
	for (int i = 0; i < numEdges; i++)
	{
		int n1 = A[i];
		int n2 = B[i];
		nodes[n1].edges.push_back(Edge { T[i], &nodes[n2] });
		nodes[n2].edges.push_back(Edge { T[i], &nodes[n1] });
	}
	
	struct Comp
	{
		Node* mid;
		int depth;
		
		inline bool operator<(const Comp& other) const
		{
			return depth > other.depth;
		}
	};
	
	std::vector<Comp> componentInfo;
	
	int numComponents = 0;
	int diameter;
	for (int i = 0; i < numNodes; i++)
	{
		if (nodes[i].component != -1)
			continue;
		nodes[i].component = numComponents++;
		initComponent(&nodes[i]);
		
		auto f1 = furthestNode(&nodes[i], nullptr);
		auto f2 = furthestNode(f1.first, nullptr);
		
		diameter = f2.second;
		
		Node* n = f1.first;
		int halfDiam = std::round(diameter / 2.0);
		int d = 0;
		while (d < halfDiam)
		{
			d += n->edges[n->diamEdge].len;
			n = n->edges[n->diamEdge].next;
		}
		
		componentInfo.push_back(Comp { n, std::max(d, diameter - d) });
	}
	
	if (numComponents == 1)
		return diameter;
	
	std::sort(componentInfo.begin(), componentInfo.end());
	
	int maxDist = diameter;
	maxDist = std::max(maxDist, componentInfo[0].depth + componentInfo[1].depth + newEdgeLen);
	if (numComponents > 2)
		maxDist = std::max(maxDist, componentInfo[1].depth + componentInfo[2].depth + newEdgeLen * 2);
	
	return maxDist;
}

Compilation message

dreaming.cpp: In function 'std::pair<Node*, int> furthestNode(Node*, Node*)':
dreaming.cpp:32:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < node->edges.size(); i++)
                  ~~^~~~~~~~~~~~~~~~~~~~
dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:73:6: warning: 'diameter' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int diameter;
      ^~~~~~~~

Subtask #1
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 70 ms 14328 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 70 ms 14328 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 70 ms 14328 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 30 ms 6780 KB Output is correct
2 Correct 40 ms 6800 KB Output is correct
3 Correct 28 ms 6772 KB Output is correct
4 Correct 30 ms 6780 KB Output is correct
5 Correct 29 ms 6780 KB Output is correct
6 Correct 32 ms 8176 KB Output is correct
7 Correct 32 ms 7028 KB Output is correct
8 Correct 29 ms 6652 KB Output is correct
9 Correct 27 ms 6640 KB Output is correct
10 Correct 30 ms 7032 KB Output is correct
11 Correct 2 ms 384 KB Output is correct
12 Correct 10 ms 5748 KB Output is correct
13 Correct 10 ms 5620 KB Output is correct
14 Correct 10 ms 5748 KB Output is correct
15 Correct 10 ms 5748 KB Output is correct
16 Correct 9 ms 5652 KB Output is correct
17 Correct 9 ms 5620 KB Output is correct
18 Correct 10 ms 5748 KB Output is correct
19 Correct 10 ms 5748 KB Output is correct
20 Correct 2 ms 384 KB Output is correct
21 Correct 2 ms 384 KB Output is correct
22 Correct 2 ms 512 KB Output is correct
23 Correct 9 ms 5620 KB Output is correct

Subtask #5
0 / 12.0

# Verdict Execution time Memory Grader output
1 Incorrect 70 ms 14328 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 70 ms 14328 KB Output isn't correct
2 Halted 0 ms 0 KB -