Submission #925274

#	Time	Username	Problem	Language	Result	Execution time	Memory
925274		TAhmed33	Road Closures (APIO21_roads)	C++17	0 / 100	2065 ms	22364 KiB

roads

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll inf = 1e14;
const int MAXN = 1e5 + 25;
vector <pair <int, int>> adj[MAXN];
ll dp[MAXN][2], cur; int n;
void dfs (int pos, int par) {
    ll sum = 0;
    for (auto j : adj[pos]) {
        if (j.first != par) {
            dfs(j.first, pos);
            sum += dp[j.first][0];
        }
    }
    dp[pos][0] = dp[pos][1] = sum;
    vector <ll> k;
    for (auto j : adj[pos]) {
        if (j.first != par) {
            k.push_back(j.second + dp[j.first][1] - dp[j.first][0]);
        }
    }
    sort(k.begin(), k.end());
    int z = (int)adj[pos].size() - (par != -1);
    ll mx1 = inf, mx2 = inf;
    sum = 0;
    k.insert(k.begin(), 0);
  int p1=max(0ll,z-cur-(par!=-1));
  int p2=max(0ll,z-cur);
    for (int j = 0; j < (int)k.size(); j++) {
        sum += k[j];
        if (j == p1) mx1 = min(mx1, sum);
        if (j == p2) mx2 = min(mx2, sum);
    }
    dp[pos][0] += mx1; dp[pos][1] += mx2;
}
vector <ll> minimum_closure_costs (int N, vector <int> u, vector <int> v, vector <int> w) {
    n = N; 
    for (int i = 0; i + 1 < n; i++) {
        adj[u[i] + 1].push_back({v[i] + 1, w[i]});
        adj[v[i] + 1].push_back({u[i] + 1, w[i]});
    }
    vector <ll> ans = {};
    for (int i = 0; i < n; i++) {
        cur = i; for (int j = 1; j <= n; j++) dp[j][0] = dp[j][1] = 0;
        dfs(1, -1);
        ans.push_back(dp[1][0]);
    }
    return ans;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 14
• Subtask 4: 0 / 10
• Subtask 5: 0 / 17
• Subtask 6: 0 / 25
• Subtask 7: 0 / 22