Submission #882887

#TimeUsernameProblemLanguageResultExecution timeMemory
882887josanneo22Chase (CEOI17_chase)C++17
100 / 100
284 ms201616 KiB
#include<bits/stdc++.h>
using namespace std;
using i64 = long long;
#define L(i,j,k) for(int i=(j);i<=(k);++i)
#define R(i,j,k) for(int i=(j);i>=(k);--i)
 
const int N=2e5+600;
i64 n,V,a[N],tmp[N];
i64 ans=0,dp[N][120][2],sum[N];
const int MN=2e5;
int head[MN<<1],ver[MN<<1],nxt[MN<<1],tot=0;
void add_edge(int x,int y){
    ver[++tot]=y;
    nxt[tot]=head[x];
    head[x]=tot;
}
#define trav(v,u) for(int j=head[u],v=ver[j];j;j=nxt[j],v=ver[j])
void update(int nw,int son,int fa){
    L(i,1,V-1) ans=max(ans,dp[nw][i][0]+dp[son][V-i][1]);
    L(i,1,V){
        dp[nw][i][0]=max({dp[nw][i][0],dp[son][i][0],dp[son][i-1][0]+sum[nw]-a[son]});
        dp[nw][i][1]=max({dp[nw][i][1],dp[son][i][1],dp[son][i-1][1]+sum[nw]-a[fa]});
    }
}
void dfs(int u,int f){
    trav(v,u){
        if(v==f) continue;
        dfs(v,u);
    }
    int cnt=0;
    L(i,1,V) dp[u][i][0]=sum[u];
    trav(v,u){
        update(u,v,f);
        tmp[++cnt]=v;
    }
    L(i,1,V) dp[u][i][0]=sum[u],dp[u][i][1]=0;
    R(i,cnt,1) update(u,tmp[i],f);
    ans=max({ans,dp[u][V][0],dp[u][V][1]});
    return;
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);
 
    std::cin>>n>>V;
    L(i,1,n) std::cin>>a[i];
    L(i,1,n-1){
        int u,v; 
        std::cin>>u>>v;
        add_edge(u,v);
        add_edge(v,u);
    }
    L(i,1,n){
    	trav(v,i){
            sum[i]+=a[v];
        }
    }
    dfs(1,0);
    cout<<ans<<'\n';
}
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