Submission #1077964

#	Time	Username	Problem	Language	Result	Execution time	Memory
1077964		Sorting	Factories (JOI14_factories)	C++17	100 / 100	6972 ms	223516 KiB

factories

#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <array>
#include <iomanip>
#include <queue>
#include <stack>
#include <numeric>
#include <cassert>
#include <cmath>
#include <random>
#include <ctime>
#include <chrono>
#include <unordered_map>

using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)x.size())
#define rep(i, a, b) for(int i = a; i < b; ++i)

template <typename T>
void remove_duplicates(vector<T> &v){
    sort(all(v));
    v.resize(unique(all(v)) - v.begin());
}

template <typename T> void chmin(T &a, T b){ a = (b < a) ? b : a; }
template <typename T> void chmax(T &a, T b){ a = (b > a) ? b : a; }

template<class T>
struct RMQ {
	vector<vector<T>> jmp;
    RMQ(){}
	RMQ(const vector<T>& V) : jmp(1, V) {
		for (int pw = 1, k = 1; pw * 2 <= sz(V); pw *= 2, ++k) {
			jmp.emplace_back(sz(V) - pw * 2 + 1);
			rep(j,0,sz(jmp[k]))
				jmp[k][j] = min(jmp[k - 1][j], jmp[k - 1][j + pw]);
		}
	}
	T query(int a, int b) {
		assert(a < b); // or return inf if a == b
		int dep = 31 - __builtin_clz(b - a);
		return min(jmp[dep][a], jmp[dep][b - (1 << dep)]);
	}
};

struct LCA {
	int T = 0;
	vi time, path, ret;
	RMQ<int> rmq;

    LCA(){}
	LCA(vector<vi>& C) : time(sz(C)), rmq((dfs(C,0,-1), ret)) {}
	void dfs(vector<vi>& C, int v, int par) {
		time[v] = T++;
		for (int y : C[v]) if (y != par) {
			path.push_back(v), ret.push_back(time[v]);
			dfs(C, y, v);
		}
	}

	int lca(int a, int b) {
		if (a == b) return a;
		tie(a, b) = minmax(time[a], time[b]);
		return path[rmq.query(a, b)];
	}
	//dist(a,b){return depth[a] + depth[b] - 2*depth[lca(a,b)];}
} lca;

const int N = 5e5 + 3;

int n, sz[N];
vector<pii> adj[N];
bool vis[N];
vi anc[N];

ll depth[N];

ll get_dist(int a, int b){
    int l = lca.lca(a, b);
    return depth[a] + depth[b] - 2 * depth[l];
}

void dfs_depth(int u, int par = -1){
    for(auto [to, w]: adj[u]){
        if(to == par) continue;
        depth[to] = depth[u] + w;
        dfs_depth(to, u);
    }
}

void dfs_sz(int u, int par = -1){
    sz[u] = 1;
    for(auto [to, w]: adj[u]){
        if(vis[to] || to == par) continue;
        dfs_sz(to, u);
        sz[u] += sz[to];
    }
}

int find_centroid(int u, int sz_root, int par = -1){
    for(auto [to, w]: adj[u]){
        if(to == par || vis[to]) continue;
        if(sz[to] >= sz_root / 2) return find_centroid(to, sz_root, u);
    }
    return u;
}

void decompose(int u, vector<int> &prevs){
    dfs_sz(u);
    int cen = find_centroid(u, sz[u]);

    prevs.push_back(cen);
    vis[cen] = true;
    anc[cen] = prevs;

    for(auto [to, w]: adj[cen]){
        if(vis[to]) continue;
        decompose(to, prevs);
    }

    prevs.pop_back();
}

void Init(int _n, int *a, int *b, int *d){
    n = _n;

    vector<vi> adj2(n + 1);
    for(int i = 0; i < n - 1; ++i){
        adj[a[i]].push_back({b[i], d[i]});
        adj[b[i]].push_back({a[i], d[i]});
        adj2[a[i]].push_back(b[i]);
        adj2[b[i]].push_back(a[i]);
    }

    lca = LCA(adj2);

    vi e{};
    decompose(0, e);

    // for(int i = 0; i < n; ++i){
        // cout << "anc of " << i << ": ";
        // for(int x: anc[i])
            // cout << x << " ";
        // cout << endl;
    // }

    dfs_depth(0);
}

const ll INF = 1e18;
ll Query(int s, int x[], int t, int y[]){
    unordered_map<int, ll> mn;
    for(int i = 0; i < s; ++i){
        int v = x[i];
        // cout << v << " ";
        for(int a: anc[v]){
            if(!mn.count(a)) mn[a] = INF;
            chmin(mn[a], get_dist(a, v));
        }
    }
    // cout << "x" << endl;

    ll ans = INF;
    for(int i = 0; i < t; ++i){
        int v = y[i];
        // cout << v << " ";
        for(int a: anc[v]){
            if(!mn.count(a)) continue;
            chmin(ans, mn[a] + get_dist(a, v));
        }
    }
    // cout << "y" << endl;

    return ans;
}

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