def PointIsOk(coords,num):
    result = True
    x = coords[num]["x"]
    y = coords[num]["y"]
    del coords[num]
    length = len(coords)
    for i in range(0,length):
        j = i-1
        ix = coords[i]["x"]
        iy = coords[i]["y"]
        jx = coords[j]["x"]
        jy = coords[j]["y"]
        if (((iy<jy) & (iy<=y) & (y<=jy) & (jy-iy)*(x-ix)>(jx-ix)*(y-iy)) |
            ((iy>jy) & (jy<=y) & (y<=iy) & (jy-iy)*(x-ix)<(jx-ix)*(y-iy))
            ):
            result = not result
    print coords, result;
    return result