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Submission #338132

# Submission time Handle Problem Language Result Execution time Memory
338132 2020-12-22T14:51:08 Z ogibogi2004 Beads and wires (APIO14_beads) C++14
57 / 100
 1000 ms 104396 KB 
#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int MAXN=2e5+6;
const ll INF=2e15;
int n;
vector<pair<int,ll> >g[MAXN];
set<pair<ll,int> >dp1[MAXN];
unordered_map<int,ll>mp1[MAXN];
unordered_map<int,ll>mp0[MAXN];
set<pair<ll,int> >dp0[MAXN];
ll dp0v[MAXN];
int root;
ll getdp1v(int u)
{
	if(dp1[u].size()==0)return -INF;
	return dp0v[u]-(*dp1[u].begin()).first;
}
struct save1
{
	int what,where;
	ll w0,w1;
};
struct save2
{
	ll mx;
	int what,where;
	ll weight,dp0vwhat;
};
stack<save1>st1;
stack<save2>st2;
void remove(int what,int where)
{
	ll w0=mp0[where][what];
	dp0v[where]-=w0;
	dp0[where].erase({w0,what});
	ll w1=mp1[where][what];
	dp1[where].erase({w1,what});
	st1.push({what,where,w0,w1});
}
void rollback1()
{
	save1 xd=st1.top();
	st1.pop();
	dp0v[xd.where]+=xd.w0;
	dp0[xd.where].insert({xd.w0,xd.what});
	dp1[xd.where].insert({xd.w1,xd.what});
}
void add(int what,int where,ll weight)
{
	ll mx=max(dp0v[what],getdp1v(what)+weight);
	dp0[where].insert({mx,what});
	dp0v[where]+=mx;
	dp1[where].insert({mx-dp0v[what]-weight,what});
	st2.push({mx,what,where,weight,dp0v[what]});
}
void rollback2()
{
	save2 xd=st2.top();st2.pop();
	dp0[xd.where].erase({xd.mx,xd.what});
	dp0v[xd.where]-=xd.mx;
	dp1[xd.where].erase({xd.mx-xd.dp0vwhat-xd.weight,xd.what});
}
void dfs(int u,int p)
{
	vector<pair<pair<ll,ll>,ll> >ch;
	vector<int>ch1;
	for(auto v:g[u])
	{
		if(v.first==p)continue;
		dfs(v.first,u);
		ch.push_back({{dp0v[v.first],getdp1v(v.first)},v.second});
		ch1.push_back(v.first);
	}
	for(int i=0;i<ch.size();++i)
	{
		dp0v[u]+=max(ch[i].first.first,ch[i].first.second+ch[i].second);
		dp0[u].insert({max(ch[i].first.first,ch[i].first.second+ch[i].second),ch1[i]});
		mp0[u][ch1[i]]=max(ch[i].first.first,ch[i].first.second+ch[i].second);
	}
	for(int i=0;i<ch.size();++i)
	{
		dp1[u].insert({max(ch[i].first.first,ch[i].first.second+ch[i].second)-ch[i].first.first-ch[i].second,ch1[i]});
		mp1[u][ch1[i]]=max(ch[i].first.first,ch[i].first.second+ch[i].second)-ch[i].first.first-ch[i].second;
	}
}
ll ans=0;
void dfs1(int u,int par)
{
	root=u;
	/*cout<<"root="<<u<<endl;
	for(int i=1;i<=n;i++)
	{
		cout<<i<<" "<<dp0v[i]<<" "<<getdp1v(i)<<endl;
	}*/
	ans=max(ans,dp0v[u]);
	for(auto v:g[u])
	{
		if(v.first==par)continue;
		root=v.first;
		remove(v.first,u);
		add(u,v.first,v.second);
		dfs1(v.first,u);
		rollback1();
		rollback2();
	}
}
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	cin>>n;
	for(int i=1;i<n;++i)
	{
		int x,y,z;
		cin>>x>>y>>z;
		g[x].push_back({y,z});
		g[y].push_back({x,z});
	}
	dfs(1,0);
	dfs1(1,0);
	cout<<ans<<"\n";
return 0;
}
/*
10
4 10 2
1 2 21
1 3 13
6 7 1
7 9 5
2 4 3
2 5 8
1 6 55
6 8 34

*/


/*
u->v
dp[u][0].erase(v)
dp[v][0].insert(u)
dp[u][1].erase(v)
dp[v][1].insert(u)



*/

Compilation message

beads.cpp: In function 'void dfs(int, int)':
beads.cpp:75:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<long long int, long long int>, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |  for(int i=0;i<ch.size();++i)
      |              ~^~~~~~~~~~
beads.cpp:81:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<long long int, long long int>, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |  for(int i=0;i<ch.size();++i)
      |              ~^~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 45804 KB Output is correct
2 Correct 28 ms 45804 KB Output is correct
3 Correct 28 ms 45804 KB Output is correct
4 Correct 28 ms 45804 KB Output is correct
5 Correct 28 ms 45804 KB Output is correct
6 Correct 28 ms 45804 KB Output is correct
7 Correct 28 ms 45804 KB Output is correct
8 Correct 28 ms 45804 KB Output is correct
9 Correct 28 ms 45804 KB Output is correct
10 Correct 28 ms 45804 KB Output is correct
11 Correct 28 ms 45804 KB Output is correct
12 Correct 28 ms 45804 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 45804 KB Output is correct
2 Correct 28 ms 45804 KB Output is correct
3 Correct 28 ms 45804 KB Output is correct
4 Correct 28 ms 45804 KB Output is correct
5 Correct 28 ms 45804 KB Output is correct
6 Correct 28 ms 45804 KB Output is correct
7 Correct 28 ms 45804 KB Output is correct
8 Correct 28 ms 45804 KB Output is correct
9 Correct 28 ms 45804 KB Output is correct
10 Correct 28 ms 45804 KB Output is correct
11 Correct 28 ms 45804 KB Output is correct
12 Correct 28 ms 45804 KB Output is correct
13 Correct 29 ms 45804 KB Output is correct
14 Correct 30 ms 45804 KB Output is correct
15 Correct 28 ms 45804 KB Output is correct
16 Correct 31 ms 45804 KB Output is correct
17 Correct 29 ms 45804 KB Output is correct
18 Correct 29 ms 45804 KB Output is correct
19 Correct 29 ms 45804 KB Output is correct
20 Correct 29 ms 45804 KB Output is correct
21 Correct 28 ms 45804 KB Output is correct
22 Correct 30 ms 45804 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 45804 KB Output is correct
2 Correct 28 ms 45804 KB Output is correct
3 Correct 28 ms 45804 KB Output is correct
4 Correct 28 ms 45804 KB Output is correct
5 Correct 28 ms 45804 KB Output is correct
6 Correct 28 ms 45804 KB Output is correct
7 Correct 28 ms 45804 KB Output is correct
8 Correct 28 ms 45804 KB Output is correct
9 Correct 28 ms 45804 KB Output is correct
10 Correct 28 ms 45804 KB Output is correct
11 Correct 28 ms 45804 KB Output is correct
12 Correct 28 ms 45804 KB Output is correct
13 Correct 29 ms 45804 KB Output is correct
14 Correct 30 ms 45804 KB Output is correct
15 Correct 28 ms 45804 KB Output is correct
16 Correct 31 ms 45804 KB Output is correct
17 Correct 29 ms 45804 KB Output is correct
18 Correct 29 ms 45804 KB Output is correct
19 Correct 29 ms 45804 KB Output is correct
20 Correct 29 ms 45804 KB Output is correct
21 Correct 28 ms 45804 KB Output is correct
22 Correct 30 ms 45804 KB Output is correct
23 Correct 39 ms 47212 KB Output is correct
24 Correct 38 ms 47212 KB Output is correct
25 Correct 39 ms 47212 KB Output is correct
26 Correct 49 ms 48620 KB Output is correct
27 Correct 51 ms 48620 KB Output is correct
28 Correct 57 ms 48644 KB Output is correct
29 Correct 68 ms 48620 KB Output is correct
30 Correct 54 ms 48492 KB Output is correct
31 Correct 57 ms 49644 KB Output is correct

Subtask #4
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 45804 KB Output is correct
2 Correct 28 ms 45804 KB Output is correct
3 Correct 28 ms 45804 KB Output is correct
4 Correct 28 ms 45804 KB Output is correct
5 Correct 28 ms 45804 KB Output is correct
6 Correct 28 ms 45804 KB Output is correct
7 Correct 28 ms 45804 KB Output is correct
8 Correct 28 ms 45804 KB Output is correct
9 Correct 28 ms 45804 KB Output is correct
10 Correct 28 ms 45804 KB Output is correct
11 Correct 28 ms 45804 KB Output is correct
12 Correct 28 ms 45804 KB Output is correct
13 Correct 29 ms 45804 KB Output is correct
14 Correct 30 ms 45804 KB Output is correct
15 Correct 28 ms 45804 KB Output is correct
16 Correct 31 ms 45804 KB Output is correct
17 Correct 29 ms 45804 KB Output is correct
18 Correct 29 ms 45804 KB Output is correct
19 Correct 29 ms 45804 KB Output is correct
20 Correct 29 ms 45804 KB Output is correct
21 Correct 28 ms 45804 KB Output is correct
22 Correct 30 ms 45804 KB Output is correct
23 Correct 39 ms 47212 KB Output is correct
24 Correct 38 ms 47212 KB Output is correct
25 Correct 39 ms 47212 KB Output is correct
26 Correct 49 ms 48620 KB Output is correct
27 Correct 51 ms 48620 KB Output is correct
28 Correct 57 ms 48644 KB Output is correct
29 Correct 68 ms 48620 KB Output is correct
30 Correct 54 ms 48492 KB Output is correct
31 Correct 57 ms 49644 KB Output is correct
32 Correct 172 ms 59884 KB Output is correct
33 Correct 168 ms 60012 KB Output is correct
34 Correct 167 ms 59940 KB Output is correct
35 Correct 695 ms 102600 KB Output is correct
36 Correct 675 ms 102600 KB Output is correct
37 Correct 686 ms 102508 KB Output is correct
38 Execution timed out 1105 ms 104396 KB Time limit exceeded
39 Halted 0 ms 0 KB -