Submission #1192545

#	Time	Username	Problem	Language	Result	Execution time	Memory
1192545		boclobanchat	Portal (BOI24_portal)	C++20	55 / 100	2058 ms	2012 KiB

Main

#include<bits/stdc++.h>
using namespace std;
const int MAXN=1e5+5;
pair<long long,long long> P[MAXN];
long long X[MAXN],Y[MAXN];
bool comp(pair<long long,long long> a,pair<long long,long long> b) { return (a.second==0)>(b.second==0); }
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
int Rand(int l,int r) { return uniform_int_distribution<int>(l,r)(rng); }
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    long long n,g=0,h=0;
    cin>>n;
    if(n<=2) return cout<<-1,0;
    for(int i=1;i<=n;i++) cin>>P[i].first>>P[i].second;
    sort(P+1,P+n+1);
    for(int i=1;i<n;i++) P[i].first-=P[i+1].first,P[i].second-=P[i+1].second,g=__gcd(g,P[i].second);
    if(!g) return cout<<-1,0;
    sort(P+1,P+n,comp);
    int l=1;
    for(int i=1;i<n;i++)
    {
    	if(P[i].second==0) h=__gcd(h,P[i].first),l++;
    	P[i].second/=g;
	}
    if(l<=n-1) for(int it=1;it<=6e7;it++)
    {
    	int i=Rand(l,n-1),j=Rand(l,n-1);
    	h=__gcd(h,(P[i].first*P[j].second-P[i].second*P[j].first));
	}
    if(!g||!h) return cout<<-1,0;
    cout<<abs(g*h);
}

• Subtask 1: 1 / 1
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 29 / 29
• Subtask 5: 15 / 15
• Subtask 6: 0 / 35