Submission #1021127

#	Time	Username	Problem	Language	Result	Execution time	Memory
1021127		adrielcp	Chase (CEOI17_chase)	C++17	0 / 100	729 ms	9452 KiB

chase

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define lld double
#define int ll
#define usaco(fname) freopen(#fname ".in","r",stdin);freopen(#fname ".out","w",stdout);
template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { os << '{'; string sep; for (const T &x : v) os << sep << x, sep = ", "; return os << '}'; }
// const ll INF = 1e18;
const int INF = 1e9;
const int mod = 1e9+7;
const lld PI = acos(-1.0);
int di[] = {1, -1, 0, 0, 1, 1, -1, -1};
int dj[] = {0, 0, 1, -1, 1, -1, 1, -1};
#define debug(x) cout << #x << ": " << x << endl;
#define add(a, b) a += b, a %= mod
#define mul(a, b) ((a % mod) * (b % mod)) % mod
#define all(x) x.begin(),x.end()

void solve() {
  int n,v;cin>>n>>v;
  vector<int> a(n);
  for (int i = 0; i < n; i++) cin >> a[i];

  vector<vector<int>> adj(n, vector<int>());
  for (int i = 0; i < n-1; i++) {
    int u,v;cin>>u>>v;u--;v--;
    adj[u].push_back(v);
    adj[v].push_back(u);
  }

  int ans = 0;
  function<void(int, int, int, int)> dfs = [&](int node, int sum, int cnt, int p) {
    int s = sum + a[node];
    for (auto children : adj[node]) {
      if (children == p) continue;
      s += a[children];
    }
    //     debug(node);
    // debug(sum);
    // debug(cnt);
    // debug(p);
    // debug(s);
    // cout << endl;

    if (cnt == v) {
      ans = max(ans, s);
      return;
    }
    
    for (auto children : adj[node]) {
      if (children != p) dfs(children, s - a[children], cnt+1, node);
    }
  };
  
  for (int i = 0; i < n; i++) dfs(i, -a[i], 1, -1);

  cout << ans << endl;
}

int32_t main() {
  ios_base::sync_with_stdio(0);cin.tie(0);
  int t=1;
  while(t--) solve();

  return 0;
}

• Subtask 1: 0 / 20
• Subtask 2: 0 / 20
• Subtask 3: 0 / 30
• Subtask 4: 0 / 30