#include <iostream>
#include <vector>

struct Point {
    double x;
    double y;
};

double orientation(const Point &A, const Point &B, const Point &C) 
{
    return (B.x - A.x) * (C.y - A.y) - (C.x - A.x) * (B.y - A.y);
}

double distance(const Point &A, const Point &B) 
{
    double dx = B.x - A.x;
    double dy = B.y - A.y;

    return dx * dx + dy * dy;
}

bool in_triangle(const Point &A, const Point &B, const Point &C, 
                 const Point &S)
{
    double o1 = orientation(A, B, S);
    double o2 = orientation(B, C, S);
    double o3 = orientation(C, A, S);

    if ((o1 > 0 && o2 > 0 && o3 > 0) ||
        (o1 < 0 && o2 < 0 && o3 < 0)) {
        return true;
    }

    return false;
}

bool in_convex_hull(const std::vector<Point> &CH, const Point &S)
{
    const int n = CH.size();

    if (orientation(CH[0], CH[1], S) < 0 ||  
        orientation(CH[0], CH[n - 1], S) < 0) {
        return false;
    }

    int l = 1;
    int r = n - 1;
    while (r - l > 1) {
        int m = l + (r - l) / 2;
        int o = orientation(CH[0], CH[m], S);
        if (o > 0) {
            r = m;
        } else if (o < 0) {
            l = m;
        } else {
            if (distance(CH[0], S) < distance(CH[0], CH[m])) {
                return true;
            } else {
                return false;
            }
        }
    }

    if (in_triangle(CH[0], CH[l], CH[r], S)) {
        return true;
    }

    return false;
}

int main(int argc, const char *argv[])
{
        
    return 0;
}