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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#60022#4809. Maximum RangexiaoyaowudiWA 70ms33416kbC++175.8kb2022-11-02 18:33:182022-11-02 18:33:21

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你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2022-11-02 18:33:21]
  • 评测
  • 测评结果:WA
  • 用时:70ms
  • 内存:33416kb
  • [2022-11-02 18:33:18]
  • 提交

answer

#include <iostream>
#include <vector>
#include <tuple>
#include <algorithm>
#include <functional>
constexpr int N(100010),inf(1.01e9);
using t3i=std::tuple<int,int,int,int>;
using veci=std::vector<int>;
int bcnt,n,m;
t3i mxm[N],mnm[N];
veci pts[N],ts[N<<1],gs[N];
#define DEBUG std::cerr<<__FUNCTION__<<std::endl
std::vector<std::pair<int,int>> eds[N],es[N];
void tarjan(int u)
{
	static std::tuple<int,int,int> stk[N];
	static int top,dfn[N],low[N],dcnt;
	dfn[u]=low[u]=++dcnt;stk[++top]={u,-1,-1};
	for(auto [v,w]:es[u])
	{
		if(!dfn[v])
		{
			tarjan(v);low[u]=std::min(low[u],low[v]);
			if(low[v]==dfn[u])
			{
				int k=++bcnt;
				pts[k].emplace_back(u);
				mxm[k]={-inf,0,0,0},mnm[k]={inf,0,0,0};
				while(1)
				{
					auto [x,y,w]=stk[top--];
					// std::cerr<<x<<" "<<y<<" "<<w<<std::endl;
					if(~y) eds[k].emplace_back(x,y),mxm[k]=std::max(mxm[k],{w,x,y,k+n}),mnm[k]=std::min(mnm[k],{w,x,y,k+n});
					else
					{
						pts[k].emplace_back(x);
						if(x==v) break;
					}
				}
				if(eds[k].size()>1)
				{
					for(int v:pts[k]) ts[k+n].emplace_back(v),ts[v].emplace_back(k+n);
				}
			}
		}
		else if(dfn[v]<dfn[u]) stk[++top]={u,v,w},low[u]=std::min(low[u],dfn[v]);
	}
}
std::pair<veci,veci> calc(const veci &vs,const veci &vall)
{
	// DEBUG;
	int l=vs.size(),u=vs[0],v=vs[l-1];
	static int fu[N],fv[N];
	static bool mk[N];
	for(int k:vs) mk[k]=true;
	std::function<void(int,int,int*)> dfs=[&dfs](int u,int fa,int *ff){ff[u]=fa;if(mk[u]) return;for(int v:gs[u]) if(!ff[v]) dfs(v,u,ff);};
	fu[u]=-1;for(int k:gs[u]) if(!mk[k] && !fu[k]) dfs(k,u,fu);
	fv[v]=-1;for(int k:gs[v]) if(!mk[k] && !fv[k]) dfs(k,v,fv);
	// std::cerr<<"❤"<<std::endl;
	if(fv[u])
	{
		// std::cerr<<"❤gyc"<<std::endl;
		veci res;
		for(int i(u);~i;i=fv[i]) res.emplace_back(i);
		// std::cerr<<"end"<<std::endl;
		return {vs,res};
	}
	int p1(1);while(!fv[vs[p1]]) ++p1;
	int p2(p1+1);while(!fu[vs[p2]]) ++p2;
	veci r1;for(int i(vs[p2]);~i;i=fu[i]) r1.emplace_back(i);std::reverse(r1.begin(),r1.end());r1.insert(r1.begin(),vs.begin()+p2+1,vs.end());
	veci r2;r2.insert(r2.begin(),vs.begin(),vs.begin()+p1);for(int i(vs[p1]);~i;i=fv[i]) r2.emplace_back(i);
	return {r1,r2};
}
veci solve_path(veci pts,int u,int v,int frb,int pre)
{
	// DEBUG;
	static int fs[N];
	static bool vis[N];
	fs[pre]=0;
	std::function<void(int,int)> dfs=[&](int u,int fa)->void{fs[u]=fa;vis[u]=true;for(int v:gs[u]) if(!vis[v] && v!=frb) dfs(v,u);};
	dfs(v,pre);
	veci ret;
	for(int k:pts) vis[k]=false;
	for(int i(u);i;i=fs[i]) ret.emplace_back(i);
	return ret;
}
std::pair<veci,veci> solve1(int idx,int u,int v,int s)
{
	// DEBUG;
	idx-=n;
	for(auto [u,v]:eds[idx]) gs[u].emplace_back(v),gs[v].emplace_back(u);
	std::pair<veci,veci> res;
	if(u==s)
	{
		res=calc({s,v},pts[idx]);
	}
	else
	{
		res=calc(solve_path(pts[idx],s,v,u,u),pts[idx]);
	}
	for(int u:pts[idx]) gs[u].clear();
	return res;
}
std::pair<veci,veci> solve2(int idx,int u,int v)
{
	// DEBUG;
	idx-=n;
	for(auto [u,v]:eds[idx]) gs[u].emplace_back(v),gs[v].emplace_back(u);
	auto res=calc(solve_path(pts[idx],u,v,0,0),pts[idx]);
	for(int u:pts[idx]) gs[u].clear();
	return res;
}
veci solve3(int idx,int u,int v,int s,int t)
{
	// DEBUG;
	idx-=n;
	for(auto [u,v]:eds[idx]) gs[u].emplace_back(v),gs[v].emplace_back(u);
	auto hp=[](std::pair<veci,veci> pr,veci vall)->veci
	{
		auto [p1,p2]=pr;
		std::reverse(p2.begin(),p2.end());
		p1.pop_back();p2.pop_back();
		p1.insert(p1.end(),p2.begin(),p2.end());
		for(int v:vall) gs[v].clear();
		return p1;
	};
	if(v==s || v==t) return hp(calc({u,v,(s^t^v)},pts[idx]),pts[idx]);
	else if(u==s || u==t) return hp(calc({v,u,(s^t^u)},pts[idx]),pts[idx]);
	auto pt=solve_path(pts[idx],v,s,t,t);
	int hu=-1,len=pt.size();
	for(int k(0);k<len;++k) if(pt[k]==u){hu=k;break;}
	if(~hu)
	{
		pt.erase(pt.begin()+1,pt.begin()+hu);
	}
	else pt.insert(pt.begin(),u);
	return hp(calc(pt,pts[idx]),pts[idx]);
}
int main()
{
	// DEBUG;
	std::ios::sync_with_stdio(false);
	std::cin.tie(0);std::cin>>n>>m;
	for(int i(1),u,v,w;i<=m;++i) std::cin>>u>>v>>w,es[u].emplace_back(v,w),es[v].emplace_back(u,w);
	tarjan(1);
	static bool vis[N<<1];
	std::function<void(int,t3i&,t3i&)> dfs1=[&dfs1](int u,t3i &mx,t3i &mn)->void
	{
		if(u>n) mx=std::max(mxm[u-n],mx),mn=std::min(mnm[u-n],mn);vis[u]=true;
		for(int v:ts[u]) if(!vis[v]) dfs1(v,mx,mn);
	};
	int ans=-1,su,sv,sk,tu,tv,tk;
	for(int i(1);i<=n;++i) if(!vis[i] && ts[i].size())
	{
		t3i mn{inf,0,0,0},mx{-inf,0,0,0};
		dfs1(i,mx,mn);
		auto [w1,e1u,e1v,v1]=mn;auto [w2,e2u,e2v,v2]=mx;
		if(w2-w1>ans)
		{
			ans=w2-w1;
			su=e1u;sv=e1v;sk=v1;
			tu=e2u;tv=e2v;tk=v2;
		}
	}
	std::cout<<ans<<std::endl;
	if(sk!=tk)
	{
		static int ff[N<<1];
		std::function<void(int,int)> dfs2=[&dfs2](int u,int fa)->void{ff[u]=fa;for(int v:ts[u])if(fa!=v) dfs2(v,u);};
		dfs2(tk,0);
		static int vs[N<<1],vc;
		for(int i(tk);i;i=ff[i]) vs[++vc]=i;
		auto [r1,r2]=solve1(sk,su,sv,vs[2]);
		for(int i=3;i<vc;i+=2)
		{
			auto [c1,c2]=solve2(vs[i],vs[i-1],vs[i+1]);
			c1.erase(c1.begin());c2.erase(c2.begin());
			r1.insert(r1.end(),c1.begin(),c1.end());
			r2.insert(r2.end(),c2.begin(),c2.end());
		}
		auto [c1,c2]=solve1(tk,tu,tv,vs[vc-1]);
		std::reverse(c1.begin(),c1.end());std::reverse(c2.begin(),c2.end());
		c1.erase(c1.begin());c2.erase(c2.begin());
		r1.insert(r1.end(),c1.begin(),c1.end());
		r2.insert(r2.end(),c2.begin(),c2.end());
		std::reverse(r2.begin(),r2.end());r1.erase(r1.end());r2.erase(r2.end());
		r1.insert(r1.end(),r2.begin(),r2.end());
		std::cout<<r1.size()<<std::endl;
		for(int v: r1) std::cout<<v<<" ";std::cout<<std::endl;
	}
	else
	{
		auto r1=solve3(sk,su,sv,tu,tv);
		std::cout<<r1.size()<<std::endl;
		for(int v:r1) std::cout<<v<<" ";std::cout<<std::endl;
	}
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 22156kb

input:

5 7
1 2 1
1 3 -2
2 3 1
3 4 3
4 5 1
1 5 -1
2 5 2

output:

5
5
1 3 4 5 2 

result:

ok ok

Test #2:

score: -100
Wrong Answer
time: 70ms
memory: 33416kb

input:

99997 100000
12238 99016 352755196
99016 25485 -412473602
25485 2440 991507552
2440 31171 -181894654
36970 2440 -800167579
2440 41865 -148191946
96629 31171 847888506
36970 95740 395546542
27992 2440 647886610
99016 29557 369124914
80795 27992 -673871966
36970 3509 573208857
57672 29557 874406776
41...

output:

1959330954
56
4697 96048 94991 31171 2440 27992 90367 94522 24616 56899 57732 80256 964 80875 37318 41262 21467 79804 22393 7822 43423 93639 10503 73944 25485 99016 29557 57672 69259 68883 94991 86274 74677 92617 86665 76022 72089 22074 96230 87712 51491 72825 3463 84407 67966 89628 84997 54073 6852...

result:

wrong answer Edge 94991-31171 does not appear in original graph