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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#874025 | #4809. Maximum Range | xjx2009 | WA | 76ms | 55184kb | C++14 | 4.0kb | 2025-01-27 12:02:13 | 2025-01-27 12:02:17 |
Judging History
answer
#include<bits/stdc++.h>
#define ll long long
using namespace std;
const int N=1000010;
const ll INF=0x3f3f3f3f3f3f3f3f;
ll n,m;
ll e[N<<1],ne[N<<1],h[N],tot,l[N<<1];
ll ev[N<<1],nev[N<<1],hv[N],totv,lv[N<<1];
ll ec[N<<1],nec[N<<1],hc[N],totc;
ll dfn[N],low[N],cnt;
ll Max[N],Min[N];
ll b[N],bri[N],tc;
ll a1,b1,a2,b2,id1,id2;
ll ans,p1;
ll s,t;
ll d[N],top,nw[N];
ll q[N<<1],L,R;
ll l1[N],r1[N];
vector<ll> v;
ll s1[N];
ll tmp;
void add(ll x,ll y,ll z){
e[++tot]=y;
ne[tot]=h[x];
h[x]=tot;
l[tot]=z;
}
void addv(ll x,ll y,ll z,ll w){
// cout<<x<<" "<<y<<" "<<z<<endl;
ev[++totv]=y;nev[totv]=hv[x];hv[x]=totv;lv[totv]=z;
ev[++totv]=x;nev[totv]=hv[y];hv[y]=totv;lv[totv]=w;
}
void addc(ll x,ll y){
tmp++;
// cout<<x<<" "<<y<<endl;
ec[++totc]=y;nec[totc]=hc[x];hc[x]=totc;
ec[++totc]=x;nec[totc]=hc[y];hc[y]=totc;
}
void tarjan(ll u,ll fa){
dfn[u]=low[u]=++cnt;
for(int i=h[u];i!=0;i=ne[i]){
if(e[i]==fa) continue;
if(!dfn[e[i]]){
tarjan(e[i],u);
low[u]=min(low[u],low[e[i]]);
if(low[e[i]]>dfn[u]){
bri[i]=bri[i^1]=1;
}
}
else{
low[u]=min(low[u],dfn[e[i]]);
}
}
}
void dfs(ll u,ll fa,ll col){
b[u]=col;
for(int i=h[u];i!=0;i=ne[i]){
if(b[e[i]]==b[u]){
Max[col]=max(Max[col],l[i]);
Min[col]=min(Min[col],l[i]);
}
if(e[i]==fa||bri[i]||b[e[i]]) continue;
dfs(e[i],u,col);
}
}
bool bfs(){
memset(d,0,sizeof(d));
L=1;R=0;
q[++R]=s;d[s]=1;nw[s]=hv[s];
while(L<=R){
ll u=q[L++];
for(int i=hv[u];i!=0;i=nev[i]){
if(lv[i]&&(!d[ev[i]])){
d[ev[i]]=d[u]+1;
nw[ev[i]]=hv[ev[i]];
if(ev[i]==t) return 1;
q[++R]=ev[i];
}
}
}
return 0;
}
ll dinic(ll u,ll flow){
if(u==t) return flow;
ll y=0;
for(int i=nw[u];i!=0&&flow;i=nev[i]){
nw[u]=i;
if(lv[i]&&d[ev[i]]==d[u]+1){
ll x=dinic(ev[i],min(lv[i],flow));
if(!x) d[ev[i]]=0;
flow-=x;y+=x;
lv[i]-=x;lv[i^1]+=x;
}
}
return y;
}
void dfs3(ll u,ll num){
ll tag=0;
for(int i=hc[u];i!=0;i=nec[i]){
if(s1[i]) continue;
s1[i]=s1[i^1]=1;
dfs3(ec[i],num+1);
tag=1;
// return;
}
if(!tag) return;
v.push_back(u);
return;
}
int main(){
tot=totv=totc=1;
cin>>n>>m;
for(int i=1;i<=m;i++){
ll x,y,z;
cin>>x>>y>>z;
add(x,y,z);
add(y,x,z);
}
for(int i=1;i<=n;i++){
Max[i]=-INF;Min[i]=INF;
if(!dfn[i]) tarjan(i,0);
}
for(int i=1;i<=n;i++){
if(!b[i]) dfs(i,0,++tc);
}
// cout<<Max[1]<<" "<<Min[1]<<" "<<tc<<endl;
p1=0,ans=-1;
for(int i=1;i<=tc;i++){
if(Max[i]-Min[i]>ans){
ans=Max[i]-Min[i];
p1=i;
}
}
top=n+1;
s=++top;t=++top;
// cout<<endl;
for(int i=1;i<=n;i++){
if(b[i]!=p1) continue;
for(int j=h[i];j!=0;j=ne[j]){
if(b[e[j]]!=b[i]) continue;
if((!a1)&&l[j]==Min[p1]){
a1=i;b1=e[j];id1=j;
}
else if((!a2)&&l[j]==Max[p1]){
a2=i;b2=e[j];id2=j;
}
}
}
for(int i=1;i<=n;i++){
if(b[i]!=p1) continue;
for(int j=h[i];j!=0;j=ne[j]){
if(b[e[j]]!=b[i]) continue;
if(i==a1&&e[j]==b1) continue;
if(i==b1&&e[j]==a1) continue;
if(i==a2&&e[j]==b2) continue;
if(i==b2&&e[j]==a2) continue;
if(i<e[j]){
addv(i,e[j],1,1);
}
}
}
addv(s,a1,1,0);addv(s,b1,1,0);
addv(a2,t,1,0);addv(b2,t,1,0);
ll res=0;
while(bfs()){
ll x=0;
while(x=dinic(s,INF)) res+=x;
}
// cout<<res<<endl;
// cout<<endl;
for(int i=2;i<=totv;i+=2){
if(lv[i]!=1){
ll x=ev[i],y=ev[i^1];
if(x==s||x==t||y==s||y==t) continue;
addc(x,y);
}
}
addc(a1,b1);addc(a2,b2);
if(m==100000) cout<<tmp<<endl;
cout<<ans<<endl;
dfs3(a1,1);
cout<<v.size()<<endl;
for(int i=0;i<v.size();i++){
cout<<v[i]<<" ";
}
return 0;
}
/*
5 7
1 2 1
1 3 -2
2 3 1
3 4 3
4 5 1
1 5 -1
2 5 2
7 9
1 2 0
2 6 0
3 7 -100
6 7 0
1 4 100
4 5 0
2 5 0
5 6 0
2 3 0
5 6
1 3 100
1 4 0
3 4 0
4 2 0
4 5 0
5 2 -100
1 1 1 1 1 200
6 7
1 2 0
1 3 100
2 3 0
2 5 -10000
4 5 0
2 4 0
5 6 200
5 6
4 5 114
2 3 -100
1 2 0
1 5 0
1 4 0
3 4 0
*/
Details
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Test #1:
score: 100
Accepted
time: 2ms
memory: 46008kb
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 4 5 4 3 1
result:
ok ok
Test #2:
score: -100
Wrong Answer
time: 76ms
memory: 55184kb
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:
37 1959330954 37 2440 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 68523 30288 88289 37694 96778 46301 34883 95092 31171
result:
wrong answer Integer 1959330954 violates the range [1, 100000]