QOJ.ac
QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#60034 | #4809. Maximum Range | xiaoyaowudi | RE | 66ms | 33132kb | C++17 | 6.3kb | 2022-11-02 18:55:34 | 2022-11-02 18:55:35 |
Judging History
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 {if(n==99996 && m==100000) std::cout<<__FUNCTION__<<std::endl;}
// #define DEBUG
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 i:vall) fu[i]=fv[i]=0,mk[i]=false;
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])
{
// if(n==99997) std::cout<<"❤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;
// std::cout<<p1<<" "<<p2<<" "<<l<<std::endl;
veci r1;for(int i(vs[p2]);~i;i=fu[i]) r1.emplace_back(i);std::reverse(r1.begin(),r1.end());r1.insert(r1.end(),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);
// for(int i(0);i<std::min<int>(5,r1.size());++i) std::cout<<r1[i]<<" ";std::cout<<std::endl;
// for(int i(0);i<std::min<int>(5,r2.size());++i) std::cout<<r2[i]<<" ";std::cout<<std::endl;
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);
if(n==99996 && m==100000){std::cout<<*ret.rbegin()<<" "<<v<<" "<<pre<<std::endl;}
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(n==99997) std::cout<<hu<<std::endl;
if(~hu)
{
pt.erase(pt.begin()+1,pt.begin()+hu);
}
else pt.insert(pt.begin(),u);
// for(int i=0;i<std::min<int>(pt.size(),10);++i) std::cout<<pt[i]<<" ";std::cout<<std::endl;
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;
}
詳細信息
Test #1:
score: 100
Accepted
time: 2ms
memory: 19936kb
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: 0
Accepted
time: 64ms
memory: 32560kb
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 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 44442 4697 96048 94991 86274 74677 92617 86665 76022 72089 22074 96230 87712 51491 72825 3463 84407 67966 89628 84997 54073 6852...
result:
ok ok
Test #3:
score: 0
Accepted
time: 56ms
memory: 32356kb
input:
99997 100000 41884 21178 -431811360 41884 42699 -450057006 36523 21178 582079730 21178 96679 615552614 63637 21178 498974417 96679 5108 235820276 75058 41884 220112636 35148 42699 589595309 36523 18002 -637739861 65854 5108 -312755792 45137 41884 -511118771 5108 31311 554050951 25335 35148 -28341059...
output:
1968439328 40 70298 33264 26071 90144 25926 52252 51434 69337 7577 5108 50088 6204 28694 41126 87303 83047 26981 54901 59612 14678 35287 78274 18331 89860 71024 99686 98098 23692 87673 42699 41884 45137 85192 38202 83711 83919 55330 71151 98733 99716
result:
ok ok
Test #4:
score: 0
Accepted
time: 66ms
memory: 33132kb
input:
99984 99999 33974 29867 335681778 33974 87468 348956829 83048 87468 320849805 29867 69456 -424530698 72457 69456 -950650074 53838 83048 755969166 85914 69456 569454441 51728 87468 -202158773 15970 29867 -865071002 15970 94894 697607001 94894 74694 616318126 33974 11496 -89287579 53838 34365 -6577379...
output:
1985932414 194 11395 92249 27866 23026 83298 1652 76013 55585 53162 41141 5525 41602 63721 42073 54251 11958 88466 28353 49296 99532 17325 75547 55727 29864 31939 52174 85999 70541 55140 80600 7311 63247 51807 97023 29296 25952 23014 84486 96848 6053 59406 91605 30363 85067 58162 86558 90720 49758 5...
result:
ok ok
Test #5:
score: 0
Accepted
time: 57ms
memory: 32520kb
input:
99988 99992 8584 11873 -811540160 68064 11873 -930246087 11873 60056 916668870 68064 82193 -859062523 60056 75072 790866030 27767 75072 357619485 75072 78221 411650300 39636 82193 264106928 6675 60056 933851261 71747 78221 -508471038 11873 92771 -665232168 34402 27767 -906494982 11873 42714 63734230...
output:
1932268861 30 93559 75593 83884 20678 16385 62720 25891 75176 34179 64174 38274 8778 99809 28745 6675 60056 75072 91957 3186 29873 5185 88236 50628 2518 83283 23798 89787 8975 26922 21107
result:
ok ok
Test #6:
score: 0
Accepted
time: 61ms
memory: 32088kb
input:
99996 99996 58191 98120 261718607 91298 98120 471683748 58191 68921 217652908 67441 91298 -731916804 78177 68921 810185021 98120 54747 -35446486 78177 2822 -409569426 91298 68058 -897038977 68921 39067 892161204 30165 78177 379543758 32418 98120 -139944101 11281 68921 422411872 37751 32418 331606200...
output:
1752928792 25 16812 65221 81854 64478 74019 46983 4369 77560 30739 1917 58464 3308 3783 48440 58191 68921 11281 34081 78216 29915 18913 85525 42296 25934 67249
result:
ok ok
Test #7:
score: -100
Runtime Error
input:
99996 100000 39127 4358 657531703 4358 66528 484843263 47215 4358 -856669390 47215 26179 -147254695 24822 39127 -635228854 81984 26179 600617794 24822 60559 327733708 39127 23879 286268283 95563 81984 -766366787 96587 24822 723252700 23879 13711 -303309809 60559 38379 992907085 60559 6012 -15086498 ...
output:
1948904917 solve1 solve_path