Taxing

#include <iostream>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <vector>
#include <utility>
using namespace std;

vector<pair<int, int> > point;

double Angle(int x1, int y1, int x2, int y2)
{  
  //acos return radian,we should transform it into degree  
  return acos((x1*x2 + y1*y2) / sqrt((x1*x1 + y1*y1)*(x2*x2 + y2*y2)))*180/M_PI;
}

int judge(int x, int y)
{
	double angle = 0;
	double tmp;
	int len=point.size();
	for(int i=0; i<len; i++)
	{	
		if(i==(len-1))
			tmp = Angle(point[i].first-x, point[i].second-y, point[0].first-x, point[0].second-y);
		else
			tmp = Angle(point[i].first-x, point[i].second-y, point[i+1].first-x, point[i+1].second-y);
		if(fabs(tmp-180.0)<1e-4)
			return 0;
		angle+=tmp;
	}
	if(fabs(angle-360.0)<1e-4)
		return 1;
	else
		return -1;

}


int main()
{
	ios::sync_with_stdio(0);
	int n, m;
	int x, y;

	while(cin>>n)
	{
		point.clear();
		while(n--)
		{
			cin>>x>>y;
			point.push_back(make_pair(x, y));
		}
		cin>>m;
		while(m--)
		{
			cin>>x>>y;
			int length = point.size();
			int flag=0;
			for(int i=0; i<length; i++)
				if(x==point[i].first && y==point[i].second)
				{
					cout<<"border"<<endl;
					flag=1;
					break;
				}
			if(flag==1) continue;
			int ans = judge(x, y);
			if(ans==1)
				cout<<"inside"<<endl;
			else if(ans==-1)
				cout<<"outside"<<endl;
			else
				cout<<"border"<<endl;
		}		
	}

	return 0;
}

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER