Submission #914999

#	Time	Username	Problem	Language	Result	Execution time	Memory
914999		KiaRez	Port Facility (JOI17_port_facility)	C++17	100 / 100	2878 ms	161684 KiB

port_facility

/*
    IN THE NAME OF GOD
*/
#include <bits/stdc++.h>

// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")

using namespace std;

typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
typedef long double ld;

#define F                                      first
#define S                                      second
#define Mp                                     make_pair
#define pb                                     push_back
#define pf                                     push_front
#define size(x)                                ((ll)x.size())
#define all(x)                                 (x).begin(),(x).end()
#define kill(x)		                           cout << x << '\n', exit(0);
#define fuck(x)                                cout << "(" << #x << " , " << x << ")" << endl
#define endl                                   '\n'

const int N = 1e6+23, lg = 21;
ll Mod = 1e9+7; //998244353;

inline ll MOD(ll a, ll mod=Mod) {a%=mod; (a<0)&&(a+=mod); return a;}
inline ll poww(ll a, ll b, ll mod=Mod) {
    ll ans = 1;
    a=MOD(a, mod);
    while (b) {
        if (b & 1) ans = MOD(ans*a, mod);
        b >>= 1;
        a = MOD(a*a, mod);
    }
    return ans;
}

int n, par[N], sz[N], val[N], vis[N], a[N], b[N];
int who[2*N], seg[2][5*N], cnt;

int getPar(int v) {return (par[v]==0 ? v : getPar(par[v]));}
int getVal(int v) {return (par[v]==0 ? val[v] : val[v]^getVal(par[v]));}
void merge(int v, int u) {
	if(getPar(v)==getPar(u)) {
		if(getVal(v) == getVal(u)) kill(0);
		return;
	}
	int x = (getVal(v) == getVal(u));
	v=getPar(v), u=getPar(u);
	if(sz[v] < sz[u]) swap(v, u);
	sz[v] += sz[u];
	par[u]=v;
	if(x==1) val[u] ^= 1;
	cnt--;
}

void build(int ind=1) {
	if(ind >= (1<<lg)) {
		int id = ind-(1<<lg)+1;
		if(id <= 2*n) {
			if(a[who[id]]==id) seg[0][ind] = who[id];
			else seg[1][ind] = who[id];
		}
		return;
	}
	build(2*ind); build(2*ind+1);
	if(seg[0][2*ind]==0 || b[seg[0][2*ind]] < b[seg[0][2*ind+1]]) seg[0][ind] = seg[0][2*ind+1];
	else seg[0][ind] = seg[0][2*ind];
	
	if(seg[1][2*ind]==0 || (seg[1][2*ind+1]>0 && a[seg[1][2*ind]]>a[seg[1][2*ind+1]])) seg[1][ind] = seg[1][2*ind+1];
	else seg[1][ind] = seg[1][2*ind];
}

void upd0(int ind, int val) {
	if(ind == 0) return;
	if(ind >= (1<<lg)) {
		seg[0][ind] = val;
	} else {
		if(seg[0][2*ind]==0 || b[seg[0][2*ind]] < b[seg[0][2*ind+1]]) seg[0][ind] = seg[0][2*ind+1];
		else seg[0][ind] = seg[0][2*ind];
	}
	upd0(ind/2, val);
}

void upd1(int ind, int val) {
	if(ind == 0) return;
	if(ind >= (1<<lg)) {
		seg[1][ind] = val;
	} else {
		if(seg[1][2*ind]==0 || (seg[1][2*ind+1]>0 && a[seg[1][2*ind]]>a[seg[1][2*ind+1]])) seg[1][ind] = seg[1][2*ind+1];
		else seg[1][ind] = seg[1][2*ind];
	}
	upd1(ind/2, val);
}

int qry0(int l, int r, int ind=1, int lc=1, int rc=(1<<lg)+1) {
	if(l>=rc || lc>=r) return 0;
	if(lc>=l && rc<=r) return seg[0][ind];
	int mid = (lc+rc)/2;
	int x=qry0(l, r, 2*ind, lc, mid), y=qry0(l, r, 2*ind+1, mid, rc);
	if(b[y] > b[x]) return y;
	return x;
}

int qry1(int l, int r, int ind=1, int lc=1, int rc=(1<<lg)+1) {
	if(l>=rc || lc>=r) return 0;
	if(lc>=l && rc<=r) return seg[1][ind];
	int mid = (lc+rc)/2;
	int x=qry1(l, r, 2*ind, lc, mid), y=qry1(l, r, 2*ind+1, mid, rc);
	if(x==0 || (a[y] < a[x] && y>0)) return y;
	return x;
}

void dfs(int v) {
	vis[v] = 1;
	upd0(a[v]+(1<<lg)-1, 0);
	upd1(b[v]+(1<<lg)-1, 0);
	while(true) {
		int u = qry0(a[v], b[v]);
		if(u==0 || b[u]<b[v]) break;
		merge(v, u);
		dfs(u);
	}
	while(true) {
		int u = qry1(a[v], b[v]);
		if(u==0 || a[u]>a[v]) break;
		merge(v, u);
		dfs(u);
	}
}

int main () {
	ios_base::sync_with_stdio(false), cin.tie(0);

	cin>>n; cnt=n;
	fill(sz+1, sz+n+1, 1);
	for(int i=1; i<=n; i++) {
		cin>>a[i]>>b[i]; 
		who[a[i]] = who[b[i]] = i;
	}

	build(1);

	for(int i=1; i<=n; i++) {
		if(vis[i] == 1) continue;
		dfs(i);
	}

	vector<pii> vec[2];
	for(int i=1; i<=n; i++) {
		vec[getVal(i)].pb({a[i], b[i]});
	}
	for(int i=0; i<2; i++) {
		sort(all(vec[i]));
		set<int> st;
		for(auto it : vec[i]) {
			auto it2 = st.lower_bound(it.F);
			if(it2!=st.end() && (*it2) < it.S) kill(0);
			st.insert(it.S);
		}
	}

	cout<<poww(2, cnt);

	return 0;
}

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