Submission #390907

#	Time	Username	Problem	Language	Result	Execution time	Memory
390907		SavicS	Factories (JOI14_factories)	C++14	0 / 100	31 ms	24988 KiB

factories

#include "factories.h"

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define ff(i,a,b) for(int i=a;i<=b;i++)
#define fb(i,b,a) for(int i=b;i>=a;i--)

using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef pair<int,int> pii;
const int maxn = 500005;
const ll inf = 1e18 + 5;

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

// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k)  print the k-th smallest number in os(0-based)

int n, q;

vector<pii> g[maxn];

int par[maxn];

int cnt[maxn];
bool bio[maxn];
void dfs_size(int v, int p) {
	cnt[v] = 1;
	for(auto c : g[v]) {
		int u = c.fi;
		int w = c.se;
		if(u == p || bio[u])continue;
		dfs_size(u, v);
		cnt[v] += cnt[u];
	}
}

int centroid(int v, int p, int vel) {
	for(auto c : g[v]) {
		int u = c.fi;
		int w = c.se;
		if(u == p || bio[u])continue;
		if(cnt[u] > vel / 2)return centroid(u, v, vel);
	}
	return v;
}

void decompose(int v, int p) {
	dfs_size(v, p);

	int cen = centroid(v, p, cnt[v]);
	bio[cen] = 1;

	par[cen] = p;
	for(auto c : g[cen]) {
		int u = c.fi;
		int w = c.se;
		if(u == p || bio[u])continue;
		decompose(u, cen);
	}

}

int d[maxn];
ll dist[maxn];
int deda[maxn][25];
void dfs(int v, int p) {
	deda[v][0] = p;
	ff(i,1,21)deda[v][i] = deda[deda[v][i - 1]][i - 1];
	for(auto c : g[v]) {
		int u = c.fi;
		int w = c.se;
		if(u != p) {
			d[u] = d[v] + 1;
			dist[u] = dist[v] + w;
			dfs(u, v);
		}
	}
}

int lca(int x, int y) {
	if(d[x] < d[y])swap(x, y);
	fb(i,21,0) {
		if((d[x] - d[y]) & (1 << i))x = deda[x][i];
	}
	fb(i,21,0) {
		if(deda[x][i] != deda[y][i]) {
			x = deda[x][i];
			y = deda[y][i];
		}
	}
	return (x == y ? x : deda[x][0]);
}

ll distance(int x, int y) {
	return dist[x] + dist[y] - 2 * dist[lca(x, y)];
}


vector<int> pamti;

ll best[maxn];
void upd(int X) {
	for(int A = X ; A != 0 ; A = par[A]) {
		pamti.pb(A);
		best[A] = min(best[A], distance(A, X));
	}
}

ll kve(int X) {
	ll ans = inf;
	for(int A = X ; A != 0 ; A = par[A]) {
		ans = min(ans, best[A] + distance(A, X));
	}
	return ans;
}

void Init(int N, int A[], int B[], int D[]) {
	n = N;
	ff(i,0,n - 2) {
		int u = A[i] + 1;
		int v = B[i] + 1;
		int w = D[i];
		g[u].pb({v, w});
		g[v].pb({u, w});
	}

	decompose(1, -1);
	dfs(1, -1);

	ff(i,1,n)best[i] = inf;
}

ll Query(int S, int X[], int T, int Y[]) {
	ff(i,0,S - 1) {
		int A = X[i] + 1;
		upd(A);
	}

	ll ans = inf;
	ff(i,0,T - 1) {
		int B = Y[i] + 1;
		ans = min(ans, kve(B));
	}

	for(auto c : pamti)best[c] = inf;
	pamti.clear();

	return ans;

}

//int main()
//{
//    ios::sync_with_stdio(false);
//    cout.tie(nullptr);
//    cin.tie(nullptr);
//	cin >> n >> q;
//	ff(i,1,n - 1){
//		int u, v, w;
//		cin >> u >> v >> w;
//		u++, v++;
//		g[u].pb({v, w});
//		g[v].pb({u, w});
//	}
//
//	decompose(1, -1);
//	dfs(1, -1);
//
//	ff(i,1,n)best[i] = inf;
//
//	while(q--){
//		int S, T;
//		cin >> S >> T;
//
//		ff(i,1,S){
//			int X;
//			cin >> X;
//			X++;
//			upd(X);
//		}
//
//		ll ans = inf;
//		ff(i,1,T){
//			int X;
//			cin >> X;
//			X++;
//			ans = min(ans, kve(X));
//		}
//
//		for(auto c : pamti)best[c] = inf;
//		pamti.clear();
//
//	}
//
//    return 0;
//}
///**
//
//
//
//// probati bojenje sahovski ili slicno
//
//**/

Compilation message (stderr)

factories.cpp: In function 'void dfs_size(int, int)':
factories.cpp:41:7: warning: unused variable 'w' [-Wunused-variable]
   41 |   int w = c.se;
      |       ^
factories.cpp: In function 'int centroid(int, int, int)':
factories.cpp:51:7: warning: unused variable 'w' [-Wunused-variable]
   51 |   int w = c.se;
      |       ^
factories.cpp: In function 'void decompose(int, int)':
factories.cpp:67:7: warning: unused variable 'w' [-Wunused-variable]
   67 |   int w = c.se;
      |       ^

• Subtask 1: 0 / 15
• Subtask 2: 0 / 18
• Subtask 3: 0 / 67