#include <bits/stdc++.h>
#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 REP(i, a) for (int i = 0; i < (a); ++i)
#define DEBUG(x) { cerr << #x << '=' << x << endl; }
#define Arr(a, l, r) { cerr << #a << " = {"; FOR(_, l, r) cerr << ' ' << a[_]; cerr << "}\n"; }
#define N 100100
#define pp pair<int, int>
#define endl '\n'
#define IO ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL)
#define taskname ""
#define bit(S, i) (((S) >> (i)) & 1)
void Max(long long &a, long long b) { a = a < b ? b : a; }
void Min(long long &a, long long b) { a = a < b ? a : b; }
using namespace std;
int n, k;
vector<int> e[N];
long long ans, a[N], DtoU[N][111], UtoD[N][111], sum[N];
long long nowUtoD[111], best2UtoD[111], best2DtoU[111], bestUtoD[111], bestDtoU[111];
int skip[N], nChild[N];
void dfs(int u, int p) {
FOR(i, 1, k) DtoU[u][i] = 0;
DtoU[u][1] = sum[u];
for (int v : e[u]) if (v != p && !skip[v]) {
FOR(i, 1, k) UtoD[v][i] = 0;
FOR(i, 1, k) {
// Choose v
if (i != 1) Max(UtoD[v][i], UtoD[u][i - 1] + sum[v] - a[u]);
else UtoD[v][i] = sum[v];
// Don't choose v
Max(UtoD[v][i], UtoD[u][i]);
Max(nowUtoD[i], UtoD[v][i]);
}
dfs(v, u);
FOR(i, 1, k) {
// Choose u
if (i != 1) Max(DtoU[u][i], DtoU[v][i - 1] + sum[u] - a[v]);
// Don't choose u
Max(DtoU[u][i], DtoU[v][i]);
}
}
}
void dfsCentroid(int u, int p) {
nChild[u] = 1;
for (int v : e[u]) if (v != p && !skip[v]) {
dfs(v, u);
nChild[u] += nChild[v];
}
}
int findCentroid(int u, int p, int total) {
for (int v : e[u]) if (v != p && !skip[v]) {
if (nChild[v] * 2 >= total) {
return findCentroid(v, u, total);
}
}
return u;
}
void Solve(int u) {
dfs(u, -1);
u = findCentroid(u, -1, nChild[u]);
skip[u] = 1;
FOR(i, 1, k) bestUtoD[i] = bestDtoU[i] = best2DtoU[i] = best2UtoD[i] = 0;
for (int v : e[u]) if (!skip[v]) {
UtoD[v][1] = sum[v];
dfs(v, u);
// Get ans
FOR(i, 0, k) {
// Don't choose u
Max(ans, bestDtoU[i] + nowUtoD[k - i]);
Max(ans, bestUtoD[i] + DtoU[v][k - i]);
// Choose u
if (i) {
Max(ans, best2DtoU[i] + sum[u] + nowUtoD[k - 1 - i] + sum[v] - a[u]);
Max(ans, best2UtoD[i] - a[u] + DtoU[v][k - 1 - i] + sum[u] - a[v]);
}
}
// cout << u << ' ' << v << ' ' << ans << '\n';
// Update
FOR(i, 1, k) {
Max(bestDtoU[i], DtoU[v][i]);
Max(bestUtoD[i], nowUtoD[i]);
Max(best2DtoU[i], DtoU[v][i] - a[v]);
Max(best2UtoD[i], nowUtoD[i] + sum[v]);
nowUtoD[i] = 0;
}
}
for (int v : e[u]) if (!skip[v])
Solve(v);
}
int main() {
#ifdef NERO
freopen("test.inp","r",stdin);
freopen("test.out","w",stdout);
double stime = clock();
#else
//freopen(taskname".inp","r",stdin);
//freopen(taskname".out","w",stdout);
#endif //NERO
IO;
cin >> n >> k;
FOR(i, 1, n) cin >> a[i];
FOR(i, 2, n) {
int u, v;
cin >> u >> v;
e[u].push_back(v);
e[v].push_back(u);
}
if (k == 0) {
cout << 0;
return 0;
}
FOR(u, 1, n) {
for (int v : e[u]) sum[u] += a[v];
}
//Arr(sum, 1, n);
Solve(1);
cout << ans;
#ifdef NERO
double etime = clock();
cerr << "\nExecution time: " << (etime - stime) / CLOCKS_PER_SEC * 1000 << " ms.\n";
#endif // NERO
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
5 ms |
2680 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
5 ms |
2680 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Execution timed out |
4041 ms |
185444 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
5 ms |
2680 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
