Submission #359093

#	Time	Username	Problem	Language	Result	Execution time	Memory
359093		AmShZ	Capital City (JOI20_capital_city)	C++11	1 / 100	37 ms	30060 KiB

capital_city

//khodaya khodet komak kon
# pragma GCC target ("avx2")
# pragma GCC optimization ("Ofast")
# pragma GCC optimization ("unroll-loops")
# include <bits/stdc++.h>
 
/*
// ordered_set 
# include <ext/pb_ds/assoc_container.hpp>
# include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
# define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update> 
*/
 
using namespace std;
 
typedef long long                                        ll;
typedef long double                                      ld;
typedef pair <int, int>                                  pii;
typedef pair <pii, int>                                  ppi;
typedef pair <int, pii>                                  pip;
typedef pair <pii, pii>                                  ppp;
typedef pair <ll, ll>                                    pll;
 
# define A                                               first
# define B                                               second
# define endl                                            '\n'
# define sep                                             ' '
# define all(x)                                          x.begin(), x.end()
# define kill(x)                                         return cout << x << endl, 0
# define SZ(x)                                           int(x.size())
# define lc                                              id << 1
# define rc                                              id << 1 | 1
# define InTheNameOfGod                                  ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
 
ll power(ll a, ll b, ll md) {return (!b ? 1 : (b & 1 ? a * power(a * a % md, b / 2, md) % md : power(a * a % md, b / 2, md) % md));}
 
const int xn = 1e4 + 10;
const int xm = 10 + 10;
const int sq = 320;
const int inf = 1e9 + 10;
const ll INF = 1e18 + 10;
const int mod = 1e9 + 7;
const int base = 257;

int n, k, c[xn], par[xm][xn], col[xm][xn], dp[xn * xm];
int H[xn], ans = inf, a[xn * xm], ptr, S;
vector <int> adj[xn], vec[xn], G[2][xn * xm], topo, nei[xn * xm];
vector <pii> E;
bitset <xn * xm> mark;

void add_edge(int v, int u){
	G[0][v].push_back(u);
	G[1][u].push_back(v);
	E.push_back({v, u});
}
void preDFS(int v){
	for (int u : adj[v]){
		if (u == par[0][v])
			continue;
		H[u] = H[v] + 1;
		par[0][u] = v;
		col[0][u] = ++ ptr;
		add_edge(ptr, v);
		preDFS(u);
	}
}
int LCA(int v, int u){
	if (H[v] > H[u])
		swap(v, u);
	for (int i = xm - 1; i >= 0; -- i)
		if ((1 << i) <= H[u] - H[v])
			u = par[i][u];
	if (v == u)
		return v;
	for (int i = xm - 1; i >= 0; -- i)
		if (par[i][v] != par[i][u])
			v = par[i][v], u = par[i][u];
	return par[0][v];
}
void DFS(int v){
	mark[v] = 1;
	for (int u : G[0][v])
		if (!mark[u])
			DFS(u);
	topo.push_back(v);
}
void SFD(int v, int mf){
	mark[v] = 1;
	a[v] = mf;
	for (int u : G[1][v])
		if (!mark[u])
			SFD(u, mf);
}

int main(){
	InTheNameOfGod;
	
	cin >> n >> k, ptr = n;
	for (int i = 0; i < n - 1; ++ i){
		int v, u;
		cin >> v >> u;
		adj[v].push_back(u);
		adj[u].push_back(v);
	}
	for (int i = 1; i <= n; ++ i)
		cin >> c[i], vec[c[i]].push_back(i);
	preDFS(1);
	for (int i = 1; i < xm; ++ i){
		for (int v = 1; v <= n; ++ v){
			par[i][v] = par[i - 1][par[i - 1][v]];
			col[i][v] = ++ ptr;
			add_edge(ptr, col[i - 1][v]);
			add_edge(ptr, col[i - 1][par[i - 1][v]]);
		}
	}
	for (int i = 1; i <= k; ++ i){
		int lca = vec[i][0];
		for (int j = 1; j < SZ(vec[i]); ++ j)
			lca = LCA(lca, vec[i][j]);
		++ ptr;
		for (int u : vec[i]){
			add_edge(ptr, u);
			add_edge(u, ptr);
			int v = u;
			for (int i = xm - 1; i >= 0; -- i){
				if ((1 << i) <= H[v] - H[lca]){
					add_edge(u, col[i][v]);
					v = par[i][v];
				}
			}
		}
	}
	for (int i = 1; i <= ptr; ++ i)
		if (!mark[i])
			DFS(i);
	mark.reset();
	reverse(all(topo));
	for (int v : topo)
		if (!mark[v])
			SFD(v, S ++);
	for (pii e : E){
		int v = e.A, u = e.B;
		if (a[v] != a[u])
			nei[a[v]].push_back(a[u]);
	}
	for (int i = 1; i <= k; ++ i)
		++ dp[a[vec[i][0]]];
	for (int v = S - 1; v >= 0; -- v){
		for (int u : nei[v])
			dp[v] += dp[u];
		if (dp[v])
			ans = min(ans, dp[v] - 1);
	}
	cout << ans << endl;
	
	return 0;
}

Compilation message (stderr)

capital_city.cpp:3: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
    3 | # pragma GCC optimization ("Ofast")
      | 
capital_city.cpp:4: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
    4 | # pragma GCC optimization ("unroll-loops")
      |

• Subtask 1: 1 / 1
• Subtask 2: 0 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 59