Submission #291476

#	Time	Username	Problem	Language	Result	Execution time	Memory
291476		groeneprof	Triangles (CEOI18_tri)	C++14	100 / 100	37 ms	2352 KiB

tri

#include <bits/stdc++.h>
#include "trilib.h"
#define P(a) do{if(debug) cout<<a<<endl;} while(false)
#define H(a) P(#a<<": "<<a)
#define FR(i,a,b) for(int i = (a); i<(b); i++)
#define F(i,n) FR(i,0,n)

const int debug = 0;

using namespace std;
bool comp(int a, int b){
	return is_clockwise(1,a,b);
}
int n;
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	n = get_n();
	vector<int> v1 = {2},v2;
	for(int i = 3; i<=n; i++){
		if(is_clockwise(1,2,i)){
			v1.push_back(i);
		}
		else{
			v2.push_back(i);
		}
	}
	P("aaaaaaaa");
	sort(v1.begin(),v1.end(),comp);
	P("a");
	sort(v2.begin(),v2.end(),comp);
	P("b");
	v1.push_back(1);
	v1.insert(v1.end(),v2.begin(),v2.end());
	deque<int> dq;
	if(debug){
		for(int i : v1){
			cout<<i<<" ";

		}
		cout<<endl;
	}
	for(int i : v1){

		while(true){
			if(dq.size()<2 || is_clockwise(dq[dq.size()-2],dq[dq.size()-1],i)) {
				dq.push_back(i);
				break;
			}
			else{
				dq.pop_back();
			}
		}
	}
	P("c");
	if(debug){
		for(int i : dq){
			cout<<i<<" ";

		}
		cout<<endl;
	}
	bool a = is_clockwise(dq[dq.size()-1],dq[0],dq[1]);
	bool b = is_clockwise(dq[dq.size()-2],dq[dq.size()-1],dq[0]);

	while(!a || !b){
		if(!a){
			dq.pop_front();
		}
		if(!b){
			dq.pop_back();
		}
		if(debug){
		for(int i : dq){
			cout<<i<<" ";

		}
		cout<<endl;
	}
		a = is_clockwise(dq[dq.size()-1],dq[0],dq[1]);
		b = is_clockwise(dq[dq.size()-2],dq[dq.size()-1],dq[0]);

	}
	give_answer(dq.size());
	return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 20 / 20
• Subtask 5: 25 / 25