Submission #1116959

#	Time	Username	Problem	Language	Result	Execution time	Memory
1116959		vjudge1	Mergers (JOI19_mergers)	C++17	0 / 100	3059 ms	58556 KiB

mergers

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define IOS ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define stdI freopen("input.txt", "r", stdin);
#define stdO freopen("output.txt", "w", stdout);
#define all(x) x.begin(), x.end()
#define mp(x, y) make_pair(x, y)
#define int long long
#define F first
#define S second
using namespace std;
using namespace __gnu_pbds;

template<typename T, template<typename> class order = less>
using ordered_set = tree<T,
    null_type, order<T>, rb_tree_tag,
    tree_order_statistics_node_update>;

typedef pair<int, int> pii;

const int MAXN = 5e5 + 100, MAXLOG = 18, MAXSQ = 500, INF = 1e18, MOD = 1e9 + 7;

vector<int> adj[MAXN];
int state[MAXN], cnts[MAXN], jaleb[MAXN];
map<int, int> dalli[MAXN];
int n, k, ans;

void un(int u, int v)
{
    if(dalli[u].size() < dalli[v].size())
    {
        dalli[u].swap(dalli[v]);
    }
    for(auto [q, w] : dalli[v])
    {
        dalli[u][q] += w;
    }
}

void dfs(int v, int p)
{
    dalli[v][state[v]]++;
    for(auto u : adj[v])
    {
        if(u != p)
        {
            dfs(u, v);
            un(v, u);
            dalli[u].clear();
        }
    }
    if(v == 1)
    {
        return;
    }
    bool bendaz = 1;
    for(int i = 1; i <= k; i++)
    {
        if(!(cnts[i] == dalli[v][i] || dalli[v][i] == 0))
        {
            bendaz = 0;
            break;
        }
    }
    if(bendaz)
    {
        jaleb[v]++; jaleb[p]++;
    }
}

void solve()
{
    cin >> n >> k;
    for(int i = 1; i < n; i++)
    {
        int u, v; cin >> u >> v;
        adj[u].push_back(v); adj[v].push_back(u);
    }
    for(int i = 1; i <= n; i++)
    {
        cin >> state[i]; cnts[state[i]]++;
    }
    dfs(1, 0);
    for(int i = 1; i <= n; i++)
    {
        ans += ((jaleb[i] == 1) ? 1 : 0);
    }
    cout << (ans + 1) / 2 << "\n";
}

int32_t main()
{
    IOS;
    int t = 1;
    //cin >> t;
    while(t--)
    {
        solve();
    }
    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 24
• Subtask 3: 0 / 14
• Subtask 4: 0 / 22
• Subtask 5: 0 / 30