Submission #928733

#	Time	Username	Problem	Language	Result	Execution time	Memory
928733		Regulus	Chase (CEOI17_chase)	C++17	40 / 100	1831 ms	524288 KiB

chase

#include <bits/stdc++.h>
#define IO ios::sync_with_stdio(false);cin.tie(0);
#define debug(x) cerr << #x << " = " << (x) << ' '
#define bug(x) cerr << (x) << ' '
#define endl cerr << '\n'
#define all(v) (v).begin(), (v).end()
#define SZ(v) (ll)(v).size()
#define lowbit(x) (x)&-(x)
#define pb emplace_back
#define F first
#define S second
using namespace std;
using ll = long long;
using pll = pair<ll, ll>;

const int N = 1e5+5;
ll a[N], sum[N], ans, m;
vector<ll> g[N], vec[N];

inline void dfs(int x, int fa)
{
    sum[x] = 0;
    for (int v : g[x]) if (v != fa) sum[x] += a[v];
    vec[x].pb(sum[x]);
    sort(all(vec[x]), greater<ll>());
    //debug(x), debug(sum[x]), endl;
    //for (int x : vec[0]) bug(x); endl;

    ll tmp = 0;
    for (int i=0; i < min(SZ(vec[x]), m); ++i) tmp += vec[x][i];
    ans = max(ans, tmp);

    for (int v : g[x])
    {
        if (v == fa) continue;
        vec[v] = vec[x];
        dfs(v, x);
    }
}

int main(void)
{ IO
    int n, i;

    cin >> n >> m;
    for (i=1; i <= n; ++i) cin >> a[i];
    for (i=0; i < n-1; ++i)
    {
        int x, y; cin >> x >> y;
        g[x].pb(y), g[y].pb(x);
    }

    for (i=1; i <= n; ++i)
    {
        for (int j=0; j <= n; ++j) vec[j].clear();
        dfs(i, 0);
        if (n > 1000) break;
    }

    cout << ans << '\n';

    return 0;
}

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