Submission #960572

#	Time	Username	Problem	Language	Result	Execution time	Memory
960572		cpptowin	Janjetina (COCI21_janjetina)	C++17	110 / 110	400 ms	51252 KiB

Main

#include <bits/stdc++.h>
#define fo(i, d, c) for (int i = d; i <= c; i++)
#define fod(i, c, d) for (int i = c; i >= d; i--)
#define maxn 1000010
#define N 1010
#define fi first
#define se second
#define pb emplace_back
#define en cout << "\n";
#define int long long
#define inf (int)1e18
#define pii pair<int, int>
#define vii vector<pii>
#define lb(x) x & -x
#define bit(i, j) ((i >> j) & 1)
#define offbit(i, j) (i ^ (1 << j))
#define onbit(i, j) (i | (1 << j))
#define vi vector<int>
template <typename T1, typename T2>
bool minimize(T1 &a, T2 b)
{
    if (a > b)
    {
        a = b;
        return true;
    }
    return false;
}
template <typename T1, typename T2>
bool maximize(T1 &a, T2 b)
{
    if (a < b)
    {
        a = b;
        return true;
    }
    return false;
}
using namespace std;
const int nsqrt = 450;
const int mod = 1e9 + 7;
struct BIT
{
    int t[maxn];
    void up(int x, int val)
    {
        x++;
        for (; x; x -= lb(x))
            t[x] += val;
    }
    int get(int x)
    {
        int ans = 0;
        x++;
        for (; x < maxn; x += lb(x))
            ans += t[x];
        return ans;
    }
} t;
int n, k;
vii ke[maxn];
int ans;
// centroid decomposition
bool is_remove[maxn];
vii event;
int sz[maxn];
int d[maxn], val[maxn];
int dfs_size(int u, int parent = -1)
{
    sz[u] = 1;
    for (auto [v, w] : ke[u])
    {
        if (v == parent or is_remove[v])
            continue;
        sz[u] += dfs_size(v, u);
    }
    return sz[u];
}
int dfs_centroid(int u, int tree_size, int parent = 0)
{
    for (auto [v, w] : ke[u])
    {
        if (v == parent or is_remove[v])
            continue;
        if (2 * sz[v] > tree_size)
            return dfs_centroid(v, tree_size, u);
    }
    return u;
}
void dfs_dist(int u, int par, int dist, int maxx)
{
    for (auto [v, w] : ke[u])
    {
        if (v == par or is_remove[v])
            continue;
        dfs_dist(v, u, dist + 1, max(maxx, w));
    }
    event.pb(maxx, dist);
    d[u] = dist;
    val[u] = maxx;
}
void solve(int val)
{
    sort(event.begin(), event.end(), greater<pii>());
    for (auto [maxx, dist] : event)
    {
        // cout << maxx << ' ' << dist << "\n";
        ans += t.get(dist) * val;
        if (maxx - dist - k >= 0)
            t.up(maxx - dist - k, 1);
    }
    // cout << ans;en;
    // cout << "xxxxxxxx\n";
    for (auto [maxx, dist] : event)
    {
        if (maxx - dist - k >= 0)
            t.up(maxx - dist - k, -1);
    }
    event.clear();
}
vi child;
void dfs_set(int u, int parent = -1)
{
    child.pb(u);
    for (auto [v, w] : ke[u])
    {
        if (v == parent or is_remove[v])
            continue;
        dfs_set(v, u);
    }
}
void build_centroid(int u)
{
    u = dfs_centroid(u, dfs_size(u));
    is_remove[u] = 1;
    // do sth
    dfs_dist(u, u, 0, 0);
    solve(1);
    for (auto [v, w] : ke[u])
    {
        if (is_remove[v])
            continue;
        dfs_set(v);
        for (int it : child)
            event.pb(val[it], d[it]);
        solve(-1);
        child.clear();
    }
    for (auto [v, w] : ke[u])
    {
        if (is_remove[v])
            continue;
        build_centroid(v);
    }
}
main()
{
#define name "TASK"
    if (fopen(name ".inp", "r"))
    {
        freopen(name ".inp", "r", stdin);
        freopen(name ".out", "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n >> k;
    fo(i, 1, n - 1)
    {
        int u, v, w;
        cin >> u >> v >> w;
        ke[u].pb(v, w);
        ke[v].pb(u, w);
    }
    build_centroid(1);
    cout << ans * 2;
}

Compilation message (stderr)

Main.cpp:156:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  156 | main()
      | ^~~~
Main.cpp: In function 'int main()':
Main.cpp:161:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  161 |         freopen(name ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:162:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  162 |         freopen(name ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 35 / 35
• Subtask 3: 60 / 60