#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
#define ar array
#define pb push_back
#define ln '\n'
#define int long long
using i64 = long long;
template <class F, class _S>
bool chmin(F &u, const _S &v){
bool flag = false;
if ( u > v ){
u = v; flag |= true;
}
return flag;
}
template <class F, class _S>
bool chmax(F &u, const _S &v){
bool flag = false;
if ( u < v ){
u = v; flag |= true;
}
return flag;
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n, k; cin >> n >> k;
vector <int> a(n);
for ( auto &u: a ) cin >> u;
vector <vector<int>> G(n);
for ( int i = 0; i + 1 < n; i++ ){
int u, v; cin >> u >> v;
--u, --v;
G[u].pb(v), G[v].pb(u);
}
if ( !k ){ return cout << "0\n", 0; }
const int inf = 1e15;
auto opt = [&](int rt){
vector <vector<ar<int,2>>> dp(n, vector <ar<int,2>> (k + 1, {-inf, -inf}));
vector <int> s(n);
auto dfs2 = [&](auto dfs2, int u, int p) -> void{
for ( auto &v: G[u] ){
if ( v != p ){
s[u] += a[v];
dfs2(dfs2, v, u);
}
}
};
dfs2(dfs2, rt, -1);
auto dfs = [&](auto dfs, int u, int p) -> void{
for ( auto &v: G[u] ){
if ( v == p ) continue;
for ( int j = 0; j <= k; j++ ){
for ( auto t: {0, 1} ){
if ( j - t < 0 ) continue;
for ( auto f: {0, 1} ){
chmax(dp[v][j][t], dp[u][j - t][f] + s[v] * t);
}
}
}
dfs(dfs, v, u);
}
};
dp[rt][1][1] = s[rt];
dfs(dfs, rt, -1);
int ret = 0;
for ( int i = 0; i < n; i++ ){
for ( int j = 0; j <= k; j++ ){
for ( auto f: {0, 1} ){
chmax(ret, dp[i][j][f]);
}
}
}
return ret;
};
int ans = 0;
for ( int i = 0; i < n; i++ ){
chmax(ans, opt(i));
if ( n > 1e3 ) break;
}
cout << ans;
cout << '\n';
}
/*
12 2
2 3 3 8 1 5 6 7 8 3 5 4
2 1
2 7
3 4
4 7
7 6
5 6
6 8
6 9
7 10
10 11
10 12
*/
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
388 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
388 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
1503 ms |
2640 KB |
Output is correct |
8 |
Correct |
107 ms |
604 KB |
Output is correct |
9 |
Correct |
91 ms |
600 KB |
Output is correct |
10 |
Correct |
1573 ms |
2464 KB |
Output is correct |
11 |
Correct |
521 ms |
1056 KB |
Output is correct |
12 |
Correct |
178 ms |
720 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
235 ms |
172992 KB |
Output is correct |
2 |
Correct |
236 ms |
173140 KB |
Output is correct |
3 |
Correct |
183 ms |
170184 KB |
Output is correct |
4 |
Correct |
49 ms |
14936 KB |
Output is correct |
5 |
Correct |
255 ms |
168784 KB |
Output is correct |
6 |
Correct |
252 ms |
170008 KB |
Output is correct |
7 |
Correct |
265 ms |
170144 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
388 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
1503 ms |
2640 KB |
Output is correct |
8 |
Correct |
107 ms |
604 KB |
Output is correct |
9 |
Correct |
91 ms |
600 KB |
Output is correct |
10 |
Correct |
1573 ms |
2464 KB |
Output is correct |
11 |
Correct |
521 ms |
1056 KB |
Output is correct |
12 |
Correct |
178 ms |
720 KB |
Output is correct |
13 |
Correct |
235 ms |
172992 KB |
Output is correct |
14 |
Correct |
236 ms |
173140 KB |
Output is correct |
15 |
Correct |
183 ms |
170184 KB |
Output is correct |
16 |
Correct |
49 ms |
14936 KB |
Output is correct |
17 |
Correct |
255 ms |
168784 KB |
Output is correct |
18 |
Correct |
252 ms |
170008 KB |
Output is correct |
19 |
Correct |
265 ms |
170144 KB |
Output is correct |
20 |
Incorrect |
263 ms |
170020 KB |
Output isn't correct |
21 |
Halted |
0 ms |
0 KB |
- |