| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 58589 | wilwxk | Chase (CEOI17_chase) | C++11 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
const int MAXN=1e5+5;
const int MAXK=102;
vector<int> g[MAXN];
int pai[MAXN], v[MAXN];
long long soma[MAXN], dp[MAXN][MAXK][2];
int n, x;
void predfs(int cur, int p) {
soma[cur]=0; pai[cur]=p;
for(auto viz : g[cur]) {
if(viz==p) continue;
predfs(viz, cur);
soma[cur]+=v[viz];
}
}
long long fazdp(int cur, int k, int flag) {
if(k<0||(k==0&&flag==0)) return 0;
if(dp[cur][k][flag]!=-1) return dp[cur][k][flag];
long long resp=0;
long long resp=0;
if(flag) resp=soma[cur];
for(auto viz : g[cur]) {
if(viz==pai[cur]) continue;
resp=max(resp, fazdp(viz, k, 0));
resp=max(resp, fazdp(viz, k-1, 1));
if(flag) resp=max(resp, resp+soma[cur]);
}
//printf("%d %d %d -> %lld\n", cur, k, flag, resp);
return dp[cur][k][flag]=resp;
}
int main() {
scanf("%d %d", &n, &x);
for(int i=1; i<=n; i++) scanf("%d", &v[i]);
for(int i=0; i<n-1; i++) {
int a, b; scanf("%d %d", &a, &b);
g[a].push_back(b); g[b].push_back(a);
}
long long respf=0;
for(int cur=1; cur<=1; cur++) {
predfs(cur, cur);
for(int i=1; i<=n; i++) for(int j=0; j<=x; j++) for(int k=0; k<2; k++) dp[i][j][k]=-1;
for(int i=0; i<=x; i++) respf=max(respf, fazdp(cur, i, 0));
for(int i=1; i<=x; i++) respf=max(respf, fazdp(cur, i-1, 1));
}
if(n<=1005) {
for(int cur=2; cur<=n; cur++) {
predfs(cur, cur); if(cur>=750) cur+=(rand()%3);
for(int i=1; i<=n; i++) for(int j=0; j<=x; j++) for(int k=0; k<2; k++) dp[i][j][k]=-1;
for(int i=0; i<=x; i++) respf=max(respf, fazdp(cur, i, 0));
for(int i=1; i<=x; i++) respf=max(respf, fazdp(cur, i-1, 1));
}
}
printf("%lld\n", respf);
}
