Poj 2318 toys

Poj_2318

You can use the cross product to determine the left or right of the online segment.

# Include <stdio. h>
# Include < String . H>
 # Define Maxd 5010
 Int N, m, X1, Y1, X2, Y2, a [maxd], B [maxd], H [maxd];
 Long   Long   Int Det ( Int X1, Int Y1,Int X2, Int Y2)
{
 Return ( Long   Long   Int ) X1 * Y2 -( Long   Long   Int ) X2 * Y1;
}
 Void Init ()
{
 Int I, J, K;
A [0 ] = B [ 0 ] = X1;
 For (I = 1 ; I <= N; I ++)
Scanf ( "  % D  " , & A [I], & B [I]);
}
 Void Solve ()
{
 Int I, J, K, X, Y, mid, Min, Max;
Memset (H, 0 ,Sizeof (H [ 0 ]) * (N + 1 ));
 For (I = 0 ; I <m; I ++)
{
Scanf ( "  % D  " , & X, & Y );
Min = 0 , Max = N + 1 ;
 For (;;)
{
Mid = (max-min )/ 2 + Min;
 If (Mid = min)
 Break ;
 If (Det (A [Mid]-B [Mid], Y1-Y2, X-B [Mid], Y-Y2) < 0 )
Min = mid;
 Else 
Max = mid;
}
++ H [Mid];
}
 For (I =0 ; I <= N; I ++)
Printf ( "  % D: % d \ n  " , I, H [I]);
}
 Int Main ()
{
 Int T = 0 ;
 While (Scanf ( "  % D  " , & N, & M, & X1, & Y1, & X2, & Y2) =6 )
{
 If (T ++)
Printf ( "  \ N  " );
Init ();
Solve ();
}
 Return   0 ;
}