Submission #625953

#	Time	Username	Problem	Language	Result	Execution time	Memory
625953		messiuuuuu	Paths (RMI21_paths)	C++17	100 / 100	285 ms	16868 KiB

Main

///
#include<bits/stdc++.h>
#define task "C"
#define ll long long
#define ld long double
#define fi first
#define se second
#define pb push_back
using namespace std;
const int MAXN = 1e5 + 5;
const ll INF = 1e18 + 5;

int n, k;
vector<pair<int, int>> Adj[MAXN];

void Input()
{
    cin >> n >> k;
    for (int i = 1; i < n; i++)
    {
        int u, v, w;
        cin >> u >> v >> w;
        Adj[u].pb({v, w});
        Adj[v].pb({u, w});
    }
}

ll up[MAXN], down[MAXN];

void DFS(int u, int par)
{
    for (auto v : Adj[u])
    {
        if (v.fi == par)
            continue;
        DFS(v.fi, u);
        down[u] = max(down[u], down[v.fi] + v.se);
    }
}

multiset<ll> s1, s2;
ll ans = 0;

void add(ll val)
{
    s1.insert(val);
    ans += val;
    if (s1.size() > k)
    {
        ans -= *s1.begin();
        s2.insert(*s1.begin());
        s1.erase(s1.begin());
    }
}

void del(ll val)
{
    if (s1.find(val) != s1.end())
    {
        ans -= val;
        s1.erase(s1.find(val));
        if (!s2.empty())
        {
            ans += *s2.rbegin();
            s1.insert(*s2.rbegin());
            s2.erase(s2.find(*s2.rbegin()));
        }
    } else
    {
        if (s2.find(val) != s2.end())
            s2.erase(s2.find(val));
    }
}

void DFS1(int u, int par)
{
    ll max1 = -INF, max2 = -INF;
    int v1, v2;
    for (auto v : Adj[u])
    {
        if (v.fi == par)
            continue;
        if (max1 < down[v.fi] + v.se)
        {
            v2 = v1;
            max2 = max1;
            v1 = v.fi;
            max1 = down[v.fi] + v.se;
        } else
            if (max2 < down[v.fi] + v.se)
            {
                v2 = v.fi;
                max2 = down[v.fi] + v.se;
            }
    }
    for (auto v : Adj[u])
    {
        if (v.fi == par)
            continue;
        if (v.fi == v1)
            up[v.fi] = max(up[u], max2);
        else
            up[v.fi] = max(up[u], max1);
        up[v.fi] += v.se;
        DFS1(v.fi, u);
        if (v.fi != v1)
            add(down[v.fi] + v.se);
    }
}

ll res[MAXN];

void DFS_cal(int u, int par)
{
    res[u] = ans;
    for (auto v : Adj[u])
    {
        if (v.fi == par)
            continue;
        del(up[v.fi] - v.se);
        add(up[v.fi]);
        del(down[v.fi] + v.se);
        add(down[v.fi]);
        DFS_cal(v.fi, u);
        add(up[v.fi] - v.se);
        del(up[v.fi]);
        add(down[v.fi] + v.se);
        del(down[v.fi]);
    }
}

void Solve()
{
    DFS(1, 0);
    DFS1(1, 0);
    add(down[1]);
    DFS_cal(1, 0);
    for (int i = 1; i <= n; i++)
        cout << res[i] << '\n';
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (fopen(task".INP","r"))
    {
        freopen(task".INP","r",stdin);
        //freopen(task".OUT","w",stdout);
    }
    Input();
    Solve();
}

Compilation message (stderr)

Main.cpp: In function 'void add(long long int)':
Main.cpp:48:19: warning: comparison of integer expressions of different signedness: 'std::multiset<long long int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   48 |     if (s1.size() > k)
      |         ~~~~~~~~~~^~~
Main.cpp: In function 'void DFS1(int, int)':
Main.cpp:78:13: warning: variable 'v2' set but not used [-Wunused-but-set-variable]
   78 |     int v1, v2;
      |             ^~
Main.cpp: In function 'int main()':
Main.cpp:148:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  148 |         freopen(task".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
Main.cpp: In function 'void DFS1(int, int)':
Main.cpp:100:9: warning: 'v1' may be used uninitialized in this function [-Wmaybe-uninitialized]
  100 |         if (v.fi == v1)
      |         ^~

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