Submission #873359

#	Time	Username	Problem	Language	Result	Execution time	Memory
873359		sleepntsheep	Paths (RMI21_paths)	C++17	48 / 100	399 ms	19284 KiB

Main

#include <cstdio>
#include <cstring>
#include <cassert>
#include <string>
#include <deque>
#include <vector>
#include <map>
#include <queue>
#include <algorithm>
#include <iostream>
#include <utility>
using namespace std;
using ll = long long;
using ld = long double;
#define ShinLena cin.tie(nullptr)->sync_with_stdio(false)

#define N 200005
#define ALL(x) x.begin(), x.end()

int n, k, sz[N];
vector<pair<int, int>> g[N];

ll dp[1001][101], dp2[N], dp3[N], dp4[N];

void dfs1(int u, int p)
{
    dp[u][0] = dp[u][1] = 0;
    sz[u] = 1;
    for (auto [w, v] : g[u]) if (v != p)
    {
        dfs1(v, u);
        for (int i = sz[u]; i >= 0; --i)
            for (int j = 1; i+j <= k && j <= sz[v]; ++j)
                dp[u][i+j] = max(dp[u][i+j], dp[u][i] + dp[v][j] + w);
        sz[u] += sz[v];
    }
}

ll oneroot(int u)
{
    memset(dp, 0xbf, sizeof dp);
    memset(sz, 0, sizeof sz);
    dfs1(u, u);
    return dp[u][k];
}

void dfs2(int u, int p)
{
    dp2[u] = 0;
    for (auto [w, v] : g[u]) if (v != p)
    {
        dfs2(v, u);
        if (dp2[v] + w >= dp2[u]) dp3[u] = dp2[u], dp2[u] = dp2[v] + w;
        else if (dp2[v] + w >= dp3[u]) dp3[u] = dp2[v] + w;
    }
}

void dfs3(int u, int p)
{
    for (auto [w, v] : g[u]) if (v != p)
    {
        if (dp2[v] + w == dp2[u]) dp4[v] = max(dp4[u] + w, dp3[u] + w);
        else dp4[v] = max(dp4[u] + w, dp2[u] + w);
        dfs3(v, u);
    }
}

int main()
{
    ShinLena;
    cin >> n >> k;
    for (int u, v, w, i = 1; i < n; ++i) cin >> u >> v >> w, g[u].emplace_back(w, v), g[v].emplace_back(w, u);

    if (k == 1)
    {
        dfs2(1, 1);
        dfs3(1, 1);
        for (int i = 1; i <= n; ++i) cout << max(dp2[i], dp4[i]) << '\n';
    }
    else if (n <= 1002)
    {
        for (int i = 1; i <= n; ++i) cout << oneroot(i) << '\n';
    }
    else if (n <= 2000)
    {
    }
    else
    {
    }

    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 0 / 20
• Subtask 5: 12 / 12
• Subtask 6: 0 / 32