제출 #57414

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
57414		Benq	Evacuation plan (IZhO18_plan)	C++14	100 / 100	1380 ms	33604 KiB

plan

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

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;

int n,m,q,l[MX],r[MX];
pi p[MX];
vi tri[MX];
vi po;

template<int SZ> struct Dijkstra {
    int dist[SZ];
    vector<pi> adj[SZ];
    priority_queue<pi,vector<pi>,greater<pi>> q;
    
    void addEdge(int a, int b, int c) {
        adj[a].pb({b,c}), adj[b].pb({a,c});
        // cout << a << " " << b << " " << c << "\n";
    }
    
    void gen() {
        fill_n(dist,SZ,MOD); 
        for (int i: po) {
            dist[i] = 0;
            q.push({0,i});
        }
    	while (q.size()) {
    		pi x = q.top(); q.pop();
    		if (dist[x.s] < x.f) continue;
    		for (pi y: adj[x.s]) if (x.f+y.s < dist[y.f]) {
    			dist[y.f] = x.f+y.s;
    			// cout << "OOPS " << x.f << " " << y.f << " " << y.s << "\n";
    			q.push({dist[y.f],y.f});
    		}
    	}
    }
};

Dijkstra<MX> D;

template<int SZ> struct DSU {
    int par[SZ], sz[SZ];
    DSU() {
        F0R(i,SZ) par[i] = i, sz[i] = 1;
    }
    
    int get(int x) { // path compression
    	if (par[x] != x) par[x] = get(par[x]);
    	return par[x];
    }
    
    bool unite(int x, int y) { // union-by-rank
    	x = get(x), y = get(y);
    	if (x == y) return 0;
    	if (sz[x] < sz[y]) swap(x,y);
    	sz[x] += sz[y], par[y] = x;
    	return 1;
    }
};

vpi v; 

void binSearch() {
    F0R(i,MX) tri[i].clear();
    F0R(i,q) tri[(l[i]+r[i])/2].pb(i);
    DSU<MX> Z = DSU<MX>();
    F0R(i,sz(v)) {
        for (auto a: D.adj[v[i].s]) if (D.dist[a.f] >= D.dist[v[i].s]) Z.unite(a.f,v[i].s);
        for (int x: tri[i]) {
            if (Z.get(p[x].f) == Z.get(p[x].s)) r[x] = i;
            else l[x] = i+1;
        }
    }
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> m;
    F0R(i,m) {
        int a,b,c; cin >> a >> b >> c;
        D.addEdge(a,b,c);
    }
    int k; cin >> k;
    F0R(i,k) {
        int g; cin >> g;
        po.pb(g);
    }
    D.gen();
    FOR(i,1,n+1) v.pb({D.dist[i],i});
    sort(all(v)); reverse(all(v));
    cin >> q;
    F0R(i,q) {
        cin >> p[i].f >> p[i].s;
        l[i] = 0, r[i] = sz(v)-1;
    }
    F0R(i,17) binSearch();
    F0R(i,q) cout << v[l[i]].f << "\n";
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46