  699

 21.1

    

             S

 					
		(i	 .)	 	( .)	 
	( .)			( .)		( .)
()	    :
1	4	 				
		 	1000	1000	1000	1000
2	4,10		+500	1500	-500	500
3	3,95		-750	750	+750	1250
4	4,15		+1000	1750	-1000	250
()	  :
1	4	 				
		 	1000	1000	1000	1000
2	4,10	:	+500	1500	-500	500
		 				
			-500	1000	-	-
		 				
			-	-	+500	1000
3	3,95	:	-750	250	+750	1750
		 				
			+750	1000	-	-
		 				
			-	-	-750	1000
4	4,15	:	+1000	2000	-1000	0
		 				
		  	2000	0		

21.3.6    

       ,    -
    . ,    .
   ,      (long)    -
. , S,       
,   .   ,     -
 (short)    .

   ,     -
 ,    .    ,   
   ,   ,    -
   . ,    ,   
   ,       ,
    .  ,    
           -
      (        ,
  . 20).

21.3.7 

 ,         -
    .        -
  .

 ,      , -
     .      -