Submission #963697

#	Time	Username	Problem	Language	Result	Execution time	Memory
963697		Cookie	Port Facility (JOI17_port_facility)	C++14	100 / 100	2912 ms	140992 KiB

port_facility

#include<bits/stdc++.h>
#include<fstream>
using namespace std;
#define sz(a) (int)a.size()
#define ALL(v) v.begin(), v.end()
#define ALLR(v) v.rbegin(), v.rend()
#define ll long long
#define pb push_back
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define ld long double
#define vt vector
#include<fstream>
#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>
#define mpp make_pair
const ld PI = 3.14159265359, prec = 1e-9;;
//using u128 = __uint128_t;
//const int x[4] = {1, 0, -1, 0};
//const int y[4] = {0, -1, 0, 1};
const ll mod = 1e9 + 7, pr = 31;
const int mxn = 1e6 + 5, mxq = 1e5 + 5, sq = 500, mxv = 5e4 + 1;
//const int base = (1 <<18);
const ll inf = 1e9 + 5, neg = -69420, inf2 = 1e14;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
// have fun!
//JOIIIIIIIIIIIIIII
int n;

pii p[mxn + 1];
int c[mxn + 1];
int st[8 * mxn + 1], st2[8 * mxn + 1];
void upd(int nd, int l, int r, int id, int v){
    if(l == r){
        st[nd] = v; return;
    }
    int mid = (l + r) >> 1;
    if(id <= mid)upd(nd << 1, l, mid, id, v);
    else upd(nd << 1 | 1, mid + 1, r, id, v);
    int cand1 = st[nd << 1], cand2 = st[nd << 1 | 1];
    st[nd] = ((p[cand1].se > p[cand2].se) ? cand1: cand2);
}
void upd2(int nd, int l, int r, int id, int v){
    if(l == r){
        st2[nd] = v; return;
    }
    int mid = (l + r) >> 1;
    if(id <= mid)upd2(nd << 1, l, mid, id, v);
    else upd2(nd << 1 | 1, mid + 1, r, id, v);
    int cand1 = st2[nd << 1], cand2 = st2[nd << 1 | 1];
    st2[nd] = ((p[cand1].fi < p[cand2].fi) ? cand1: cand2);
}
int get(int nd, int l, int r, int ql, int qr){
    if(ql > r || qr < l)return(0);
    if(ql <= l && qr >= r)return(st[nd]);
    int mid = (l + r) >> 1;
    int cand1 = get(nd << 1, l, mid, ql, qr), cand2 = get(nd << 1 | 1, mid + 1, r, ql, qr);
    return((p[cand1].se > p[cand2].se) ? cand1 : cand2);
}
int get2(int nd, int l, int r, int ql, int qr){
    if(ql > r || qr < l)return(0);
    if(ql <= l && qr >= r)return(st2[nd]);
    int mid = (l + r) >> 1;
    int cand1 = get2(nd << 1, l, mid, ql, qr), cand2 = get2(nd << 1 | 1, mid + 1, r, ql, qr);
    return((p[cand1].fi < p[cand2].fi) ? cand1 : cand2);
}
void dfs(int s){
    
    upd(1, 1, 2 * n, p[s].fi, 0); upd2(1, 1, 2 * n, p[s].se, 0);
    while(1){
        int v = get(1, 1, 2 * n, p[s].fi, p[s].se);
        if(p[v].se > p[s].se){
            c[v] = c[s] ^ 1;
            dfs(v);
        }else{
            break;
        }
    }
    while(1){
        int v = get2(1, 1, 2 * n, p[s].fi, p[s].se);
        if(p[v].fi < p[s].fi){
            c[v] = c[s] ^ 1; dfs(v);
        }else{
            break;
        }
    }
}
void solve(){
    cin >> n;
    p[0].fi = inf; p[0].se = 0;
    for(int i = 1; i <= n; i++)cin >> p[i].fi >> p[i].se;
    sort(p + 1, p + n + 1);
    for(int i = 1; i <= n; i++){
        upd(1, 1, 2 * n, p[i].fi, i); upd2(1, 1, 2 * n, p[i].se, i);
    }
    int cnt = 0;
    for(int i = 1; i <= n; i++)c[i] = -1;
    for(int i = 1; i <= n; i++){
        if(c[i] == -1){
            c[i] = 0; dfs(i); ++cnt;
        }
    }
    set<int>s1, s2;
    for(int i = 1; i <= n; i++){
        if(c[i] == 0){
            auto it = s1.lower_bound(p[i].fi);
            if(it == s1.end() || (*it) > p[i].se){
                s1.insert(p[i].se);
            }else{
                cout << 0; return;
            }
        }else{
            auto it = s2.lower_bound(p[i].fi);
            if(it == s2.end() || (*it) > p[i].se){
                s2.insert(p[i].se);
            }else{
                cout << 0; return;
            }
        }
    }
    int ans = 1;
    for(int i = 0; i < cnt; i++)ans = (ans * 2) % mod;
    cout << ans;
}
signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    //freopen("DATA.inp", "r", stdin);
    //freopen("DATA.out", "w", stdout);
    int tt; tt = 1;
    while(tt--){
        solve();
 
    }
    return(0);
}

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