/*-------------------------------------------------------------------------
  Include files:
--------------------------------------------------------------------------*/

#include <stdio.h>
#include <stdlib.h>
#include <math.h>


/*=========================================================================
  Constants and definitions:
==========================================================================*/

/* put your #defines and typedefs here*/



/*-------------------------------------------------------------------------
  The main program. (describe what your program does here)
 -------------------------------------------------------------------------*/
 struct box
 {
     unsigned short size;
     unsigned int friends[5];
 };
/*--------------------------------------------------------------------------------*/
 void create_boxes(struct box[10][10], float*x_p, float*y_p, unsigned int friends);
 int Is_Complete(float number);
 int Quarter(float x,float y);
 void the_best_friend(float *my_co, struct box boxes[10][10], float *x_p, float *y_p, float *best_friend);

/*----------------------------------------------------------------------------------*/

int main()
{
 unsigned int number_of_friends;
 float *x_Coordinates,*y_Coordinates;
 float my_x,my_y;
 unsigned int i;
 struct box boxes[10][10]={{{0,{0,0,0,0,0}}}};
 float my_co_array[2];
 float best_friend[2];

 printf(">Please enter the number of your friends:\n");
 printf(">Please enter your coordinates:\n");
 printf(">Please enter your friends' coordinates:\n");
 scanf("%u %f %f",&number_of_friends,&my_x,&my_y);
 x_Coordinates=(float *)malloc((number_of_friends) * sizeof(float));
 y_Coordinates=(float *)malloc((number_of_friends) * sizeof(float));

 for(i=0;i<number_of_friends;i++)
 {
   scanf("%f %f",& x_Coordinates[i],& y_Coordinates[i]);
 }
my_co_array[0]=my_x;
my_co_array[1]=my_y;

create_boxes(boxes,x_Coordinates,y_Coordinates,number_of_friends);

/*for(i=0;i<10;i++)
{
    for(j=0;j<10;j++)
    {
     printf("box [%u][%u] size is : %d\n",i,j,boxes[i][j].size);
    }

}
*/
the_best_friend(my_co_array,boxes,x_Coordinates,y_Coordinates,best_friend);

printf("your best friend location is : %f %f \n",best_friend[0],best_friend[1]);

 free(x_Coordinates);
 free(y_Coordinates);
  return 0;
}


void create_boxes(struct box boxes[10][10], float *x_p, float *y_p, unsigned int friends)
{
  int co_x=0,co_y=0;
  int m,n;
  unsigned int i;
  for(i=0;i<friends;i++)
  {
      switch(Quarter(x_p[i],y_p[i]))
      {
       case 1:
       {  co_x=(int)(x_p[i]);
         if(Is_Complete(y_p[i]))
           co_y=(int)(y_p[i]);
         else co_y=((int)(y_p[i]))+1;
       }break;

       case 2:
       {
           if(Is_Complete(x_p[i]))
             co_x=(int)(x_p[i]);
           else
             co_x=(int)(x_p[i])-1;
           if(Is_Complete(y_p[i]))
             co_y=(int)(y_p[i]);
           else co_y=((int)(y_p[i]))+1;
       }break;

       case 3:
       {
           if(Is_Complete(x_p[i]))
             co_x=(int)(x_p[i]);
           else
             co_x=(int)(x_p[i])-1;
            if(Is_Complete(y_p[i]))
             co_y=(int)(y_p[i]);
           else co_y=(int)(y_p[i]);
       }break;

       case 4:
       {
           co_x=(int)x_p[i];
            if(Is_Complete(y_p[i]))
            co_y=(int)(y_p[i]);
           else co_y=(int)(y_p[i]);

       }break;

      }

  if(co_y==-5)
  {
   m=4-co_y;
   n=5+co_x;
   if(co_x==5)
    n=4+co_x;
  }
  else if(co_x==5)
  {
      m=5-co_y;
      n=4+co_x;
  }
  else
  {
      m=5-co_y;
      n=5+co_x;
  }


boxes[m][n].friends[boxes[m][n].size]=i;
boxes[m][n].size++;
  }

 return ;
}

int Is_Complete(float number)
{
    float a;
    a=number;
    return((int)(number)==a);
}
int Quarter(float x,float y)
{
    if(x>0 && y>0) return 1;
    if(x<0 && y>0) return 2;
    if(x<0 && y<0) return 3;
    return 4;
}

void the_best_friend(float *my_co, struct box boxes[10][10], float *x_p, float *y_p, float *best_friend)
{
    unsigned int my_box_x,my_box_y,shell_size,i,j,friend_index;
    float min_dis=10.0,temp_dis;
    int temp [2];
    float friend_x_temp,friend_y_temp;
    unsigned begin_row,begin_col,temp_col;
    switch(Quarter(my_co[0],my_co[1]))
      {
       case 1:
       {  temp[0]=(int)(my_co[0]);
         if(Is_Complete(my_co[1]))
           temp[1]=(int)(my_co[1]);
         else temp[1]=((int)(my_co[1]))+1;
       }break;

       case 2:
       {
           if(Is_Complete(my_co[0]))
             temp[0]=(int)(my_co[0]);
           else
             temp[0]=(int)(my_co[0])-1;
           if(Is_Complete(my_co[1]))
             temp[1]=(int)(my_co[1]);
           else temp[1]=((int)(my_co[1]))+1;
       }break;

       case 3:
       {
           if(Is_Complete(my_co[0]))
             temp[0]=(int)(my_co[0]);
           else
             temp[0]=(int)(my_co[0])-1;
            if(Is_Complete(my_co[1]))
             temp[1]=(int)(my_co[1]);
           else temp[1]=(int)(my_co[1]);
       }break;

       case 4:
       {
           temp[0]=(int)my_co[0];
            if(Is_Complete(my_co[1]))
            temp[1]=(int)(my_co[1]);
           else temp[1]=(int)(my_co[1]);

       }break;

      }
       if(temp[1]==-5)
      {
        my_box_x=4-temp[1];
        my_box_y=5+temp[0];
        if(temp[0]==5)
        my_box_y=4+temp[0];
      }
    else if(temp[0]==5)
     {
        my_box_x=5-temp[1];
        my_box_y=4+temp[0];
     }
    else
    {
       my_box_x=5-temp[1];
       my_box_y=5+temp[0];
    }
/*----------------------------------------------------------------------*/
      if(my_box_x==0)
       { begin_row=0;
         shell_size=4;
        if(my_box_y==0)
        {
            begin_col=0;
        }
        else if(my_box_y==9)
        {
         begin_col=8;
        }
        else
        {
            shell_size=6;
            begin_col=my_box_y-1;
        }
       }
       else if(my_box_x==9)
       {
          begin_row=8;
          shell_size=4;
        if(my_box_y==0)
        {
            begin_col=0;
        }
        else if(my_box_y==9)
        {
         begin_col=8;
        }
        else
        {
            shell_size=6;
            begin_col=my_box_y-1;
        }
       }

    else
    {
     begin_row=my_box_x-1;
     shell_size=6;
     if(my_box_y==0) begin_col=0;
     else if(my_box_y==9) begin_col=8;
     else { shell_size=9; begin_col=my_box_y-1; }
    }
    /*matches the shell size and the begin row and col for each case of the nine*/
/*-----------------------------------------------------------------------------*/
    temp_col=begin_col;
    for(i=0;i<shell_size;i++)
    {
        for(j=0;j<boxes[begin_row][begin_col].size;j++)
        {

               friend_index=boxes[begin_row][begin_col].friends[j];
               friend_x_temp=x_p[friend_index];
               friend_y_temp=y_p[friend_index];


               temp_dis=pow(((my_co[0])-(friend_x_temp)),2)+pow(((my_co[1])-(friend_y_temp)), 2);
               if(temp_dis<min_dis)
                {
                  min_dis=temp_dis;
                  best_friend[0]=friend_x_temp;
                  best_friend[1]=friend_y_temp;
                }
        }
        begin_col++;
        if(((i+1)%3)==0 && ((shell_size==6) || (shell_size==9)))
        {
            begin_row++;
            begin_col=temp_col;
        }
        else if(((i+1)%2)==0 && (shell_size==2))
        {
         begin_row++;
         begin_col=temp_col;
        }

    }

 return ;


}