Submission #1023785

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023785		dozer	Dreaming (IOI13_dreaming)	C++14	18 / 100	34 ms	23132 KiB

dreaming

#include <bits/stdc++.h>
using namespace std;
#include "dreaming.h"
#define sp " "
#define endl "\n"
#define pb push_back
#define pii pair<int, int>
#define st first
#define nd second
#define fileio() freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout)
#define fastio() cin.tie(0), ios_base::sync_with_stdio(0)
#define mid (l + r) / 2
#define LL node * 2
#define RR node * 2 + 1
#define ll long long
#define MAXN 300005


const int modulo = 1e9 + 7;
const ll INF = 2e18 + 7;


int maks[MAXN], sub_maks[MAXN], vis[MAXN];
vector<pii> adj[MAXN];


int dfs2(int node, int root){
	int ans = 0;
	for (auto i : adj[node]){
		if (i.st == root) continue;
		ans = max(ans, dfs2(i.st, node) + i.nd);
	}
	return sub_maks[node] = ans;
}

int dfs(int node, int root, int m){
	vis[node] = 1;
	maks[node] = max(m, sub_maks[node]);
	int ans = maks[node];

	vector<array<int, 3>> v;
	for (auto i : adj[node]){
		if (i.st == root) continue;
		v.pb({sub_maks[i.st] + i.nd, i.st, i.nd});
	}

	sort(v.begin(), v.end());
	for (int i = 0; i < v.size(); i++){
		int to = v[i][1], w = v[i][2];
		int add = m;
		if (i + 1 < v.size()) add = max(add, v.back()[0]);
		else add = max(add, v[v.size() - 2][0]);
		ans = min(ans, dfs(to, node, add + w));
	}
	return ans;
}


int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
    for (int i = 0; i < M; i++){
    	A[i]++, B[i]++;
    	adj[A[i]].pb({B[i], T[i]});
    	adj[B[i]].pb({A[i], T[i]});
    }

    priority_queue<int> q;
    for (int i = 1; i <= N; i++){
    	if (vis[i]) continue;
    	int tmp = dfs2(i, 0);
    	int to = dfs(i, 0, 0);
    	q.push(to);
    }

    int ans = 0;
    while(!q.empty()){
    	int a = q.top();
    	q.pop();
    	if (q.empty()) break;
    	int b = q.top();
    	q.pop();
    	int neww = max(a, b + L);
    	ans = max(ans, a + b + L);
    	q.push(neww);
    }

    return ans;
}

Compilation message (stderr)

dreaming.cpp: In function 'int dfs(int, int, int)':
dreaming.cpp:48:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |  for (int i = 0; i < v.size(); i++){
      |                  ~~^~~~~~~~~~
dreaming.cpp:51:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |   if (i + 1 < v.size()) add = max(add, v.back()[0]);
      |       ~~~~~~^~~~~~~~~~
dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:69:10: warning: unused variable 'tmp' [-Wunused-variable]
   69 |      int tmp = dfs2(i, 0);
      |          ^~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 10
• Subtask 3: 0 / 23
• Subtask 4: 18 / 18
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23