C++漫步者问题模拟

#include <iostream>
 
 

  #include <string>
 
 

  #include <cmath>
 
 

  #include <cstdlib>
 
 

  #include <ctime>
 
 

  using namespace std;
 
 

  
 

  //随机漫步问题
 
 

  
 

  class Vector
 
 

  {
 
 

  private:
 
 
 double mag;//极坐标长度
 
 
 double dir;//极坐标方向
 
 

  public:
 
 
 Vector();
 
 
 Vector(double m,double d);
 
 
 double magval()
 
 
 {
 
 
 return mag;
 
 
 }
 
 
 double dirval()
 
 
 {
 
 
 return dir;
 
 
 }
 
 
 Vector operator+(const Vector &v)
 
 
 {
 
 
 //先化作直角坐标
 
 
 float x=mag*cos(dir);
 
 
 float y=mag*sin(dir);
 
 

  
 
 float v_x=v.mag*cos(v.dir);
 
 
 float v_y=v.mag*sin(v.dir);
 
 

  
 
 float x_total=x+v_x;
 
 
 float y_total=y+v_y;
 
 

  
 
 return Vector(sqrt((x_total*x_total+y_total*y_total)),atan2(y_total,x_total));
 
 
 }
 
 

  
 

  };
 
 

  Vector::Vector()
 
 

  {
 
 
 mag=0;
 
 
 dir=0;
 
 

  }
 
 

  Vector::Vector(double m,double d)
 
 

  {
 
 
 mag=m;
 
 
 dir=d;
 
 

  }
 
 

  int main()
 
 

  {
 
 
 srand(time(0));
 
 
 Vector result(0.0,0.0);
 
 
 double direction;
 
 
 int steps=0;
 
 
 //直至漫步到距离为50的地方才停止
 
 
 while(result.magval()<50)
 
 
 {
 
 
 //随机生成指定步数的向量
 
 
 direction=rand()%360;
 
 
 Vector temp(2,direction);
 
 
 //走一步
 
 
 result=result+temp;
 
 
 steps++;
 
 
 }
 
 
 cout<<"steps="<<steps<<endl;
 
 

  
 
 return 0;
 
 

  }