CODE:

#include "DxLib.h"
#include 
#include "MyVector.h"
using namespace std;
using namespace MyVector;
char Key[256];

class Arm{
private:
	enum Constant{
	NUMBONE = 10
	};
	struct Bone{
		Vector position;
		double sin;
		double cos;
		double length;
		Bone():sin(0),cos(1),length(0){}
	};
	vector BoneList;
	Vector target;
public:        
	Arm():BoneList(NUMBONE){
		for(unsigned int i=0;i::iterator it=BoneList.begin();it!=BoneList.end();++it){
			Vector dlt= target-it->position;
			double rad = atan2(dlt.y,dlt.x);
			it->sin = sin(rad);
			it->cos = cos(rad);
			target=target-dlt*(it->length/dlt.Length());
		}
	}      
	void CalculatePosition(){
		for(vector::reverse_iterator it=BoneList.rbegin();it!=BoneList.rend()-1;){
			(++it)->position=it->position+VRotate2D(Vector(1,0),it->sin,it->cos)*(it->length);
		}
	}   
	void Draw(){
		for(vector::iterator it=BoneList.begin();it!=BoneList.end();++it){
			DrawCircle(it->position.x , it->position.y, 10 , 0x00ff00);
			DrawLine(it->position.x,it->position.y,it->position.x+it->cos*it->length,it->position.y+it->sin*it->length,0x00ff00);
		}
	}
};
class Arm_honest_to_a_fault{
	Vector target;
	Vector position[3];
	enum{Length = 100};
public:
	Arm_honest_to_a_fault(){
		for(int i=0;i
#define VTOL 0.000001
namespace MyVector{
	class Vector{
	public:
		double x;
		double y;
		double z;

		inline Vector():x(0),y(0),z(0){}
		inline Vector(double init_x, double init_y, double init_z = 0)
			:x(init_x),y(init_y),z(init_z){
		}
		inline void SetValue(double init_x, double init_y, double init_z = 0){
			x=init_x;
			y=init_y;
			z=init_z;
		}
		inline Vector(const Vector& other){
			x=other.x;
			y=other.y;
			z=other.z;
		}
		inline Vector& operator=(const Vector& other){
			x=other.x;
			y=other.y;
			z=other.z;
			return *this;
		}
		inline ~Vector(){}

		inline operator bool() const {return x||y||z;};
		inline bool operator==(const Vector& other) const{
			return abs(other.x-x)VTOL||abs(other.y-y)>VTOL||abs(other.z-z)>VTOL;
		}
		//以下固有メンバ関数
		inline double Length() const{ //ベクトルの大きさ
			return sqrt(x*x+y*y+z*z);
		}
		inline double Magnitude() const{
			return sqrt(x*x+y*y+z*z);
		}
		inline void Normalize(){	//ベクトルの正規化
			double m = sqrt(x*x+y*y+z*z);
			if(mMagnitude();
			if(abs(mag1)x=v->x*cos-v->y*sin;
		v->y=v->x*sin+v->y*cos;
		return *v;
	}
	inline double VDistanceSq(const Vector& v1, const Vector& v2){
		return (v1-v2)*(v1-v2);
	}
	
	inline double VEuclideanDistance(const Vector& v1, const Vector& v2){
		return (v1-v2).Length();
	}
	
	inline double VManhattanDistance(const Vector& v1, const Vector& v2){
		double x = v1.x-v2.x;
		double y = v1.y-v2.y;
		double z = v1.z-v2.z;
		if(x<0)x=-x;
		if(y<0)y=-y;
		if(z<0)y=-z;
		return x+y+z;
	}
}