Submission #1274841

#	Time	Username	Problem	Language	Result	Execution time	Memory
1274841		vulestamenkovic	Zvijezda (COCI19_zvijezda)	C++20	0 / 110	61 ms	2000 KiB

zvijezda

#include<bits/stdc++.h>
#define int long long
#define MAXN (int)1e5+5
#define pii pair<int,int>
#define fi first
#define se second
using namespace std;
int x[MAXN],y[MAXN];
int query(int s1,int s2,array<int,2>t){
	int j=0;
	while(s1==j||s2==j){
		j++;
	}
	int o=(x[s2]-x[s1])*(t[1]-y[s2])-(t[0]-x[s2])*(y[s2]-y[s1]),
		o2=(x[s2]-x[s1])*(y[j]-y[s2])-(x[j]-x[s2])*(y[s2]-y[s1]);
	return (abs(o+o2)==abs(o)+abs(o2));
}
void solve() {
	int t,n,q;cin>>t>>n;
	for(int i=0;i<n;i++){
		cin>>x[i]>>y[i];
	}
	cin>>q;
	int z=0;
	while(q--){
		int a,b;cin>>a>>b;
		a^=(t*z*z*z);
		b^=(t*z*z*z);
		int o=query(0,1,{a,b}),
			o2=query(n/2,n/2+1,{a,b});
		if(o==o2){
			z+=o;
			cout<<(o?"DA\n":"NE\n");continue;
		}
		int l=2,r=n/2,ans=1;
		while(l<=r){
			int s=(l+r)/2;
			if(query(s-1,s,{a,b})==o){
				ans=s;
				l=s+1;
			}else{
				r=s-1;
			}
		}
		l=n/2+2,r=n;
		int ans2=n/2+1;
		while(l<=r){
			int s=(l+r)/2;
			if(query(s-1,s%n,{a,b})==o2){
				ans2=s;
				l=s+1;
			}else{
				r=s-1;
			}
		}
		r=ans+n-ans2;
		//cout<<o<<' '<<r<<'\n';
		if((o&&r>n/2)||(!o&&r<n/2)){z++;
			cout<<"DA\n";
		}else{
			cout<<"NE\n";
		}
	}
}
int32_t main() {
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	int32_t T=1;//cin>>T;
	while(T--) {
		solve();
	}
	return 0;
}

• Subtask 1: 0 / 20
• Subtask 2: 0 / 30
• Subtask 3: 0 / 60