#include<bits/stdc++.h>
using namespace std;
#define all(fl) fl.begin(),fl.end()
#define pb push_back
#define fi first
#define se second
#define for1(i,j,k) for(int i=j;i<=k;i++)
#define for2(i,j,k) for(int i=j;i>=k;i--)
#define for3(i,j,k,l) for(int i=j;i<=k;i+=l)
#define lb lower_bound
#define ub upper_bound
#define sz(a) (int)a.size()
#define pii pair<int,int>
#define pli pair<long long,int>
#define pil pair<int,long long>
#define gcd __gcd
#define lcm(x,y) x*y/__gcd(x,y)
const int maxn=2e5+9;
const long long inf=1e15;
vector<pil>a[maxn];
int n,k;
struct ver{
long long maxdis;
int num;
long long mindis;
ver (){
maxdis=0;
num=0;
mindis=inf;
}
}b[maxn];
vector<int>take;
void dfs(int u,int par,long long mid){
//cerr<<u<<'\n';
if (sz(a[u])==1&&a[u][0].fi==par){
//cerr<<u<<'\n';
for (auto v:a[u]){
if (v.se>mid){
b[u].mindis=0;
b[u].maxdis=-1;
//cerr<<u<<'\n';
take.pb(u);
b[u].num=1;
}
else {
b[u].maxdis=v.se;
}
}
return;
}
for (auto v:a[u]){
if (v.fi==par)continue;
dfs(v.fi,u,mid);
b[u].maxdis=max(b[u].maxdis,b[v.fi].maxdis);
b[u].num+=b[v.fi].num;
b[u].mindis=min(b[u].mindis,b[v.fi].mindis+v.se);
}
if (b[u].mindis+b[u].maxdis<=mid){
b[u].maxdis=-1;
}
//if (u==8)cout<<b[u].mindis<<" "<<b[u].maxdis<<'\n';
for (auto v:a[u]){
if (v.fi==par){
if (b[u].maxdis==-1){
continue;
}
if (b[u].maxdis+v.se>mid){
b[u].num++;
//cerr<<u<<'\n';
take.pb(u);
b[u].mindis=0;
b[u].maxdis=-1;
}
else {
b[u].maxdis+=v.se;
}
}
}
if (u==1){
if (b[u].maxdis!=-1){
b[u].num++;
take.pb(u);
//cerr<<u<<'\n';
}
}
}
bool check(long long mid){
take.clear();
for1(i,1,n){
b[i]=ver();
}
//cerr<<b[8].num<<'\n';
dfs(1,0,mid);
if (b[1].num>k)return false;
return true;
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
//freopen("KTREE.INP","r",stdin);
//freopen("KTREE.OUT","w",stdout);
cin>>n>>k;
for1(i,1,n-1){
int u,v;
long long w;
cin>>u>>v>>w;
a[u].pb({v,w});
a[v].pb({u,w});
}
long long l=0,r=2e14,ans=2e14;
while (l<=r){
long long mid=(l+r)/2;
if (check(mid)){
r=mid-1;
ans=mid;
}
else l=mid+1;
}
cout<<ans<<'\n';
check(ans);
for (auto v:take)cout<<v<<" ";
//cout<<check(7);
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
9684 KB |
Output is correct |
2 |
Incorrect |
4 ms |
9592 KB |
Unexpected end of file - int32 expected |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
337 ms |
35996 KB |
Output is correct |
2 |
Correct |
357 ms |
38104 KB |
Output is correct |
3 |
Correct |
311 ms |
23940 KB |
Output is correct |
4 |
Correct |
1211 ms |
23472 KB |
Output is correct |
5 |
Correct |
906 ms |
23036 KB |
Output is correct |
6 |
Correct |
1016 ms |
23116 KB |
Output is correct |
7 |
Correct |
1018 ms |
21840 KB |
Output is correct |
8 |
Correct |
1014 ms |
22496 KB |
Output is correct |
9 |
Correct |
1220 ms |
22864 KB |
Output is correct |
10 |
Correct |
1052 ms |
23188 KB |
Output is correct |
11 |
Correct |
763 ms |
24908 KB |
Output is correct |
12 |
Correct |
648 ms |
24768 KB |
Output is correct |
13 |
Correct |
806 ms |
26180 KB |
Output is correct |
14 |
Correct |
640 ms |
23312 KB |
Output is correct |
15 |
Correct |
599 ms |
22908 KB |
Output is correct |
16 |
Correct |
636 ms |
24292 KB |
Output is correct |
17 |
Correct |
690 ms |
23588 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
351 ms |
38616 KB |
Output is correct |
2 |
Correct |
364 ms |
37800 KB |
Output is correct |
3 |
Correct |
315 ms |
36428 KB |
Output is correct |
4 |
Correct |
328 ms |
36292 KB |
Output is correct |
5 |
Correct |
355 ms |
39272 KB |
Output is correct |
6 |
Correct |
378 ms |
38760 KB |
Output is correct |
7 |
Correct |
396 ms |
39780 KB |
Output is correct |
8 |
Correct |
360 ms |
38176 KB |
Output is correct |
9 |
Correct |
347 ms |
37880 KB |
Output is correct |
10 |
Correct |
316 ms |
37308 KB |
Output is correct |
11 |
Correct |
352 ms |
36176 KB |
Output is correct |
12 |
Incorrect |
385 ms |
39740 KB |
Unexpected end of file - int32 expected |
13 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
9684 KB |
Output is correct |
2 |
Incorrect |
4 ms |
9592 KB |
Unexpected end of file - int32 expected |
3 |
Halted |
0 ms |
0 KB |
- |