// g++ -std=c++14
/*
Today might be the chance to grasp the chance to let your talent bloom.
May be tomorrow, the day after, or next year...
May be even when you are 30. I'm not sure if physique has anything to do with it
but if you think that it will never come, it probably never will.
- Tooru Oikawa.
*/
#include<bits/stdc++.h>
typedef long long ll;
typedef long double lld;
using namespace std;
#define endl "\n"
#define fi first
#define se second
#define MEMS(a,b) memset(a,b,sizeof(a))
#define _ ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define __ freopen("input.txt","r",stdin);freopen("output.txt","w",stdout);
#define all(c) c.begin(),c.end()
#define pii pair<int, int>
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l, int r)
{
uniform_int_distribution<int> uid(l, r);
return uid(rng);
}
#define tr(...) cout<<__FUNCTION__<<' '<<__LINE__<<" = ";trace(#__VA_ARGS__, __VA_ARGS__)
template<typename S, typename T>
ostream& operator<<(ostream& out,pair<S,T> const& p){out<<'('<<p.fi<<", "<<p.se<<')';return out;}
template<typename T>
ostream& operator<<(ostream& out,vector<T> const& v){
ll l=v.size();for(ll i=0;i<l-1;i++)out<<v[i]<<' ';if(l>0)out<<v[l-1];return out;}
template <typename T>
ostream &operator<<(ostream &out, set<T> const &v) {
for (auto i = v.begin(); i != v.end(); i++)
out << (*i) << ' ';
return out;
}
template <typename T>
ostream &operator<<(ostream &out, multiset<T> const &v) {
for (auto i = v.begin(); i != v.end(); i++)
out << (*i) << ' ';
return out;
}
template <typename T, typename V>
ostream &operator<<(ostream &out, map<T, V> const &v) {
for (auto i = v.begin(); i != v.end(); i++)
out << "\n" << (i->first) << ":" << (i->second);
return out;
}
template<typename T>
void trace(const char* name, T&& arg1){cout<<name<<" : "<<arg1<<endl;}
template<typename T, typename... Args>
void trace(const char* names, T&& arg1, Args&&... args){
const char* comma = strchr(names + 1, ',');cout.write(names, comma-names)<<" : "<<arg1<<" | ";trace(comma+1,args...);}
const int N = 1e4 + 2;
vector<vector<pii>> g(N);
int dp[N][N][2]; // 0-> for coming back, 1 -> staying
int n, k, x;
const int inf = 1e9 + 1;
int sub[N];
void dfs(int v, int p) {
sub[v] = 1;
dp[v][1][0] = 0;
dp[v][1][1] = 0;
for (auto u : g[v]) {
if (u.fi == p) continue;
dfs(u.fi, v);
sub[v] += sub[u.fi];
}
int c = 1;
for (auto u : g[v]) {
if (u.fi == p) continue;
c += sub[u.fi];
c = min(c, k);
for (int q = 1; q >= 0; q--) {
if (q == 0) {
for (int j = c; j > 0; j--) {
for (int i = 1; i <= sub[u.fi] && j - i >= 0; i++) {
if (dp[u.fi][i][0] != inf) {
dp[v][j][0] = min(dp[v][j][0], dp[u.fi][i][0] + dp[v][j - i][0] + (u.se * 2));
}
}
}
} else if (q == 1) {
for (int j = c; j > 0; j--) {
for (int i = 0; i <= sub[u.fi] && j - i >= 0; i++) {
if (dp[u.fi][i][0] != inf) {
dp[v][j][1] = min(dp[v][j][1], dp[u.fi][i][1] + dp[v][j - i][0] + u.se);
dp[v][j][1] = min(dp[v][j][1], dp[u.fi][i][0] + dp[v][j - i][1] + (u.se) * 2);
}
}
}
}
}
}
dp[v][0][0] = dp[v][0][1] = 0;
}
int solve() {
for (int i = 0; i < N; i++)
for (int j = 0; j < N; j++)
for (int k = 0; k < 2; k++)
dp[i][j][k] = inf;
cin >> n >> k >> x;
for (int i = 0; i < n - 1; i++) {
int v, u, w;
cin >> v >> u >> w;
g[u].push_back({v, w});
g[v].push_back({u, w});
}
dfs(x, 0);
cout << dp[x][k][1] << endl;
return 0;
}
int32_t main(){ _
int t;
// cin >> t;
t = 1;
while (t--) solve();
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
409 ms |
783816 KB |
Output is correct |
2 |
Correct |
406 ms |
783672 KB |
Output is correct |
3 |
Correct |
400 ms |
783608 KB |
Output is correct |
4 |
Correct |
424 ms |
783736 KB |
Output is correct |
5 |
Correct |
413 ms |
783608 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
432 ms |
784124 KB |
Output is correct |
2 |
Correct |
431 ms |
784120 KB |
Output is correct |
3 |
Correct |
578 ms |
784504 KB |
Output is correct |
4 |
Correct |
497 ms |
784248 KB |
Output is correct |
5 |
Correct |
466 ms |
784180 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
432 ms |
784124 KB |
Output is correct |
2 |
Correct |
431 ms |
784120 KB |
Output is correct |
3 |
Correct |
578 ms |
784504 KB |
Output is correct |
4 |
Correct |
497 ms |
784248 KB |
Output is correct |
5 |
Correct |
466 ms |
784180 KB |
Output is correct |
6 |
Correct |
418 ms |
784120 KB |
Output is correct |
7 |
Correct |
558 ms |
784376 KB |
Output is correct |
8 |
Correct |
425 ms |
784248 KB |
Output is correct |
9 |
Correct |
415 ms |
784120 KB |
Output is correct |
10 |
Correct |
427 ms |
784264 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
409 ms |
783816 KB |
Output is correct |
2 |
Correct |
406 ms |
783672 KB |
Output is correct |
3 |
Correct |
400 ms |
783608 KB |
Output is correct |
4 |
Correct |
424 ms |
783736 KB |
Output is correct |
5 |
Correct |
413 ms |
783608 KB |
Output is correct |
6 |
Correct |
432 ms |
784124 KB |
Output is correct |
7 |
Correct |
431 ms |
784120 KB |
Output is correct |
8 |
Correct |
578 ms |
784504 KB |
Output is correct |
9 |
Correct |
497 ms |
784248 KB |
Output is correct |
10 |
Correct |
466 ms |
784180 KB |
Output is correct |
11 |
Correct |
418 ms |
784120 KB |
Output is correct |
12 |
Correct |
558 ms |
784376 KB |
Output is correct |
13 |
Correct |
425 ms |
784248 KB |
Output is correct |
14 |
Correct |
415 ms |
784120 KB |
Output is correct |
15 |
Correct |
427 ms |
784264 KB |
Output is correct |
16 |
Correct |
667 ms |
784120 KB |
Output is correct |
17 |
Correct |
2730 ms |
784120 KB |
Output is correct |
18 |
Execution timed out |
3131 ms |
784444 KB |
Time limit exceeded |
19 |
Halted |
0 ms |
0 KB |
- |