#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#define MOD 1000000007
#define INF 1e18
#define fi first
#define se second
#define endl "\n"
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORD(i,a,b) for(int i=a;i>=b;i--)
#define sz(a) ((int)(a).size())
#define pi 3.14159265359
#define TASKNAME "parkovi"
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res >= val){ res = val; return true; }; return false; }
using namespace std;
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
typedef vector<int> vi;
const int MAXN = 3e5 + 9;
vector<int> g[MAXN];
iii edge[MAXN];
int n, k;
namespace sub1{
bool checkSubtask1(){
return n <= 20;
}
int dist[21];
vector<int> SetVertice;
void bfs(){
priority_queue<ii, vector<ii>, greater<ii> > q;
fill(dist + 1, dist + 1 + n, INF);
for(auto x: SetVertice){
dist[x] = 0;
q.push({0, x});
}
while(!q.empty()){
int u = q.top().se;
int du = q.top().fi;
q.pop();
if (du > dist[u]) continue;
for(auto idedge: g[u]){
int v = edge[idedge].se.fi + edge[idedge].se.se - u;
int w = edge[idedge].fi;
if (dist[v] > dist[u] + w){
dist[v] = dist[u] + w;
q.push({dist[v], v});
}
}
}
}
void solveSubtask1(){
int res = INF;
int msk = 0;
for(int i = 1; i < (1 << n); i++){
SetVertice.clear();
if (__builtin_popcount(i) != k) continue;
for(int j = 0; j < n; j++){
if (i & (1 << j)) SetVertice.pb(j + 1);
}
bfs();
if (minimize(res, *max_element(dist + 1, dist + 1 + n))) msk = i;
}
cout << res << endl;
vector<int> park;
for(int i = 0; i < n; i++){
if (msk & (1 << i)) park.pb(i + 1);
}
for(auto x: park){
cout << x << " ";
}
cout << endl;
}
}
namespace sub2{
bool checkSubtask2(){
return k == 1;
}
int par[MAXN], depth[MAXN];
void dfs(int u,int p){
for(auto idedge: g[u]){
int v = edge[idedge].se.fi + edge[idedge].se.se - u;
int w = edge[idedge].fi;
if (v == p) continue;
depth[v] = depth[u] + w;
par[v] = u;
dfs(v, u);
}
}
void reset(){
fill(par + 1, par + 1 + n, -1);
fill(depth + 1, depth + 1 + n, 0);
}
void solveSubtask2(){
dfs(1, -1);
int root = max_element(depth + 1, depth + 1 + n) - depth;
reset();
dfs(root, -1);
int furthest = max_element(depth + 1, depth + 1 + n) - depth;
vector<int> diameter;
int res = INF, tmp = furthest, chosen = 0;
while(tmp != root) {
if (minimize(res, max(depth[tmp], depth[furthest] - depth[tmp]))){
chosen = tmp;
}
tmp = par[tmp];
}
cout << res << endl;
cout << chosen << endl;
}
}
namespace sub3{
bool checkSubtask3(){
for(int i = 1; i < n; i++){
if (edge[i].se.fi != i or edge[i].se.se != i + 1) return false;
}
return true;
}
int chosen[MAXN];
bool check(int mid){
int minimum = 0;
queue<int> q;
q.push(1);
int tmp = k;
int cur = mid;
while(!q.empty()){
int u = q.front();
// cout << u << ' ' << cur << endl;
if (cur < 0){
cur = mid;
tmp--;
}
q.pop();
for(auto idedge: g[u]){
int v = edge[idedge].se.fi + edge[idedge].se.se - u;
int w = edge[idedge].fi;
if (v == u - 1) continue;
if (cur - w < 0){
tmp--;
cur = mid - w;
}
else cur = cur - w;
q.push(v);
}
}
return tmp >= 0;
}
void SolveSubtask3(){
int l = 1;
int r = 2e14;
int res= 0;
while(l <= r){
int mid = (l + r) >> 1;
if (check(mid)) {
res = mid;
r = mid - 1;
}
else l = mid + 1;
}
queue<int> q;
q.push(1);
int cur = res;
while(!q.empty()){
int u = q.front();
q.pop();
if (cur < 0){
cur = res;
k--;
chosen[u] = 1;
}
for(auto idedge: g[u]){
int v = edge[idedge].se.fi + edge[idedge].se.se - u;
int w = edge[idedge].fi;
if (v == u - 1) continue;
if (cur - w < 0){
k--;
cur = res - w;
chosen[u] = 1;
}
else cur -= w;
q.push(v);
}
}
for(int i = 1; i <= n; i++){
if (!chosen[i] and k > 0) chosen[i] = 1, k--;
}
cout << res << endl;
for(int i = 1; i <= n; i++){
if (chosen[i]) cout << i << " ";
}
cout << endl;
}
}
main()
{
fast;
if (fopen(TASKNAME".inp","r")){
freopen(TASKNAME".inp","r",stdin);
freopen(TASKNAME".out","w",stdout);
}
cin >> n >> k;
for(int i = 1; i < n; i++){
int u, v, w;
cin >> u >> v >> w;
edge[i] = {w, {u, v}};
g[u].pb(i);
g[v].pb(i);
}
if (sub1::checkSubtask1()) return sub1::solveSubtask1(), 0;
if (sub2::checkSubtask2()) return sub2::solveSubtask2(), 0;
if (sub3::checkSubtask3()) return sub3::SolveSubtask3(), 0;
}
Compilation message
Main.cpp: In function 'bool sub3::check(long long int)':
Main.cpp:136:13: warning: unused variable 'minimum' [-Wunused-variable]
136 | int minimum = 0;
| ^~~~~~~
Main.cpp: At global scope:
Main.cpp:210:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
210 | main()
| ^~~~
Main.cpp: In function 'int main()':
Main.cpp:214:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
214 | freopen(TASKNAME".inp","r",stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:215:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
215 | freopen(TASKNAME".out","w",stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
11100 KB |
Output is correct |
2 |
Correct |
8 ms |
11100 KB |
Output is correct |
3 |
Correct |
6 ms |
11100 KB |
Output is correct |
4 |
Correct |
5 ms |
11100 KB |
Output is correct |
5 |
Correct |
6 ms |
11096 KB |
Output is correct |
6 |
Correct |
17 ms |
11100 KB |
Output is correct |
7 |
Correct |
23 ms |
11096 KB |
Output is correct |
8 |
Correct |
10 ms |
11096 KB |
Output is correct |
9 |
Correct |
72 ms |
11140 KB |
Output is correct |
10 |
Correct |
9 ms |
11100 KB |
Output is correct |
11 |
Correct |
41 ms |
11100 KB |
Output is correct |
12 |
Correct |
80 ms |
11144 KB |
Output is correct |
13 |
Correct |
7 ms |
11096 KB |
Output is correct |
14 |
Correct |
39 ms |
11096 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
63 ms |
38972 KB |
Output is correct |
2 |
Correct |
77 ms |
41080 KB |
Output is correct |
3 |
Correct |
71 ms |
31028 KB |
Output is correct |
4 |
Correct |
123 ms |
29940 KB |
Output is correct |
5 |
Correct |
104 ms |
29308 KB |
Output is correct |
6 |
Correct |
129 ms |
29544 KB |
Output is correct |
7 |
Correct |
116 ms |
27476 KB |
Output is correct |
8 |
Correct |
134 ms |
28200 KB |
Output is correct |
9 |
Correct |
144 ms |
28524 KB |
Output is correct |
10 |
Correct |
153 ms |
29324 KB |
Output is correct |
11 |
Correct |
86 ms |
30184 KB |
Output is correct |
12 |
Correct |
91 ms |
30292 KB |
Output is correct |
13 |
Correct |
103 ms |
31956 KB |
Output is correct |
14 |
Correct |
78 ms |
29812 KB |
Output is correct |
15 |
Correct |
82 ms |
29204 KB |
Output is correct |
16 |
Correct |
92 ms |
29928 KB |
Output is correct |
17 |
Correct |
83 ms |
28756 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
165 ms |
25764 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
11100 KB |
Output is correct |
2 |
Correct |
8 ms |
11100 KB |
Output is correct |
3 |
Correct |
6 ms |
11100 KB |
Output is correct |
4 |
Correct |
5 ms |
11100 KB |
Output is correct |
5 |
Correct |
6 ms |
11096 KB |
Output is correct |
6 |
Correct |
17 ms |
11100 KB |
Output is correct |
7 |
Correct |
23 ms |
11096 KB |
Output is correct |
8 |
Correct |
10 ms |
11096 KB |
Output is correct |
9 |
Correct |
72 ms |
11140 KB |
Output is correct |
10 |
Correct |
9 ms |
11100 KB |
Output is correct |
11 |
Correct |
41 ms |
11100 KB |
Output is correct |
12 |
Correct |
80 ms |
11144 KB |
Output is correct |
13 |
Correct |
7 ms |
11096 KB |
Output is correct |
14 |
Correct |
39 ms |
11096 KB |
Output is correct |
15 |
Correct |
63 ms |
38972 KB |
Output is correct |
16 |
Correct |
77 ms |
41080 KB |
Output is correct |
17 |
Correct |
71 ms |
31028 KB |
Output is correct |
18 |
Correct |
123 ms |
29940 KB |
Output is correct |
19 |
Correct |
104 ms |
29308 KB |
Output is correct |
20 |
Correct |
129 ms |
29544 KB |
Output is correct |
21 |
Correct |
116 ms |
27476 KB |
Output is correct |
22 |
Correct |
134 ms |
28200 KB |
Output is correct |
23 |
Correct |
144 ms |
28524 KB |
Output is correct |
24 |
Correct |
153 ms |
29324 KB |
Output is correct |
25 |
Correct |
86 ms |
30184 KB |
Output is correct |
26 |
Correct |
91 ms |
30292 KB |
Output is correct |
27 |
Correct |
103 ms |
31956 KB |
Output is correct |
28 |
Correct |
78 ms |
29812 KB |
Output is correct |
29 |
Correct |
82 ms |
29204 KB |
Output is correct |
30 |
Correct |
92 ms |
29928 KB |
Output is correct |
31 |
Correct |
83 ms |
28756 KB |
Output is correct |
32 |
Incorrect |
165 ms |
25764 KB |
Output isn't correct |
33 |
Halted |
0 ms |
0 KB |
- |