Submission #987016

#	Time	Username	Problem	Language	Result	Execution time	Memory
987016		GrindMachine	Port Facility (JOI17_port_facility)	C++17	100 / 100	1638 ms	242592 KiB

port_facility

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

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e6 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

template<typename T>
struct segtree1 {
    // https://codeforces.com/blog/entry/18051

    /*=======================================================*/

    struct data {
        ll mx,ind;
    };

    data neutral = {-inf2,-1};

    data merge(data &left, data &right) {
        data curr;
        if(left.mx >= right.mx) curr = left;
        else curr = right;
        return curr;
    }

    void create(int i, T v) {
        tr[i] = {v.ff,v.ss};
    }

    void modify(int i, T v) {
        tr[i] = {v.ff,v.ss};
    }

    /*=======================================================*/

    int n;
    vector<data> tr;

    segtree1() {

    }

    segtree1(int siz) {
        init(siz);
    }

    void init(int siz) {
        n = siz;
        tr.assign(2 * n, neutral);
    }

    void build(vector<T> &a, int siz) {
        rep(i, siz) create(i + n, a[i]);
        rev(i, n - 1, 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
    }

    void pupd(int i, T v) {
        modify(i + n, v);
        for (i = (i + n) >> 1; i; i >>= 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
    }

    data query(int l, int r) {
        data resl = neutral, resr = neutral;

        for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
            if (l & 1) resl = merge(resl, tr[l++]);
            if (!(r & 1)) resr = merge(tr[r--], resr);
        }

        return merge(resl, resr);
    }
};

template<typename T>
struct segtree2 {
    // https://codeforces.com/blog/entry/18051

    /*=======================================================*/

    struct data {
        ll mn,ind;
    };

    data neutral = {inf2,-1};

    data merge(data &left, data &right) {
        data curr;
        if(left.mn <= right.mn) curr = left;
        else curr = right;
        return curr;
    }

    void create(int i, T v) {
        tr[i] = {v.ff,v.ss};
    }

    void modify(int i, T v) {
        tr[i] = {v.ff,v.ss};
    }

    /*=======================================================*/

    int n;
    vector<data> tr;

    segtree2() {

    }

    segtree2(int siz) {
        init(siz);
    }

    void init(int siz) {
        n = siz;
        tr.assign(2 * n, neutral);
    }

    void build(vector<T> &a, int siz) {
        rep(i, siz) create(i + n, a[i]);
        rev(i, n - 1, 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
    }

    void pupd(int i, T v) {
        modify(i + n, v);
        for (i = (i + n) >> 1; i; i >>= 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
    }

    data query(int l, int r) {
        data resl = neutral, resr = neutral;

        for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
            if (l & 1) resl = merge(resl, tr[l++]);
            if (!(r & 1)) resr = merge(tr[r--], resr);
        }

        return merge(resl, resr);
    }
};

void solve(int test_case)
{
    ll n; cin >> n;
    vector<pll> a(n+5);
    rep1(i,n) cin >> a[i].ff >> a[i].ss;
    sort(a.begin()+1,a.begin()+n+1);

    vector<pll> lx(2*n+5,{inf2,-1}), rx(2*n+5,{-inf2,-1});
    rep1(i,n) lx[a[i].ss] = {a[i].ff,i};
    rep1(i,n) rx[a[i].ff] = {a[i].ss,i};
    
    segtree1<pll> st1(2*n+5);
    segtree2<pll> st2(2*n+5);
    st1.build(rx,2*n+1);
    st2.build(lx,2*n+1);

    vector<ll> vis(n+5);
    vector<ll> col(n+5);

    ll ans = 1;
    
    rep1(i,n){
        if(vis[i]) conts;
        queue<ll> q;
        q.push(i);
        vis[i] = 1;
        st1.pupd(a[i].ff,{-inf2,-1});
        st2.pupd(a[i].ff,{inf2,-1});

        while(!q.empty()){
            ll u = q.front();
            q.pop();
            
            auto [l,r] = a[u];

            while(true){
                auto [mxr,v] = st1.query(l,r);
                if(mxr < r) break;
                if(!vis[v]){
                    q.push(v);
                    vis[v] = 1;
                    col[v] = col[u]^1;   
                }

                st1.pupd(a[v].ff,{-inf2,-1});
            }

            while(true){
                auto [mnl,v] = st2.query(l,r);
                if(mnl > l) break;
                if(!vis[v]){
                    q.push(v);
                    vis[v] = 1;
                    col[v] = col[u]^1;
                }

                st2.pupd(a[v].ss,{inf2,-1});
            }
        }

        ans = ans*2%MOD;
    }

    rep(c,2){
        stack<ll> stk;
        rep1(i,2*n){
            ll j = max(lx[i].ss,rx[i].ss);
            if(col[j] != c) conts;
            if(a[j].ff == i){
                stk.push(j);
            }
            else{
                if(stk.empty()){
                    ans = 0;
                    break;
                }

                if(stk.top() != j){
                    ans = 0;
                }
                
                stk.pop();
            }
        }
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 56 / 56
• Subtask 4: 22 / 22