Submission #113624

#	Time	Username	Problem	Language	Result	Execution time	Memory
113624		aminra	Port Facility (JOI17_port_facility)	C++14	22 / 100	6012 ms	63708 KiB

port_facility

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
const int MOD = (int)1e9 + 7;
const int MAXN = (int)2e6 + 3;
const int infint = (int)2e9;
const ll inf = (ll)2e18;
int cyc = 0;
int a[MAXN], b[MAXN], n, c[MAXN];
vector<int> G[MAXN];
void dfs(int u, int color)
{
	c[u] = color;
	for (auto v : G[u])
		if(!c[v])
			dfs(v, 3 - color);
		else
		if(c[v] == c[u])
			cyc = 1;
}
int pwr(int a, int b)
{
	if(b == 0)
		return 1;
	int c = pwr(a, b >> 1);
	c = 1LL * c * c % MOD;
	if(b & 1)
		c = 1LL * c * a % MOD;
	return c;
}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	cin >> n;
	for (int i = 0; i < n; i++)
		cin >> a[i] >> b[i];
	
	for (int i = 0; i < n; i++)
		for (int j = i + 1; j < n; j++)
			if((a[i] < a[j] && a[j] < b[i] && b[j] > b[i]) || (a[j] < a[i] && a[i] < b[j] && b[i] > b[j]))
				G[i].push_back(j), G[j].push_back(i);
	int sz = 0;
	for (int i = 0; i < n; i++)
		if(!c[i])
			dfs(i, 1), sz++;
	
	if(cyc)
		return cout << 0, 0;
	cout << pwr(2, sz);
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22