00000000: 11 00 00 DF 01 40 00 90 00 E0 00 30 01 DF 01 DF |.....@.....0....|
00000010: 01 DF 01 DF 01 00 00 00 00 00 00 17 09 00 00 0D |................|
00000020: 20 20 20 20 20 20 20 20 73 61 6D 65 20 20 6D 61 | same ma|
00000030: 6E 6E 65 72 20 20 61 73 20 61 20 72 65 61 6C 20 |nner as a real |
00000040: 63 68 65 63 6B 65 72 20 62 6F 61 72 64 2C 20 20 |checker board, |
00000050: 61 6E 20 38 20 20 62 79 20 20 38 20 20 6D 61 74 |an 8 by 8 mat|
00000060: 72 69 78 2E 20 20 0D 0D 20 20 20 20 20 20 20 20 |rix. .. |
00000070: 41 6E 6F 74 68 65 72 20 20 77 61 79 20 74 6F 20 |Another way to |
00000080: 61 63 68 69 65 76 65 20 74 68 65 20 73 61 6D 65 |achieve the same|
00000090: 20 65 6E 64 20 69 73 20 74 6F 20 64 65 66 69 6E | end is to defin|
000000A0: 65 20 74 68 65 20 64 6F 75 62 6C 65 20 0D 0D 20 |e the double .. |
000000B0: 20 20 20 20 20 20 20 61 72 72 61 79 20 20 61 73 | array as|
000000C0: 20 69 6E 20 74 68 65 20 6E 65 78 74 20 6C 69 6E | in the next lin|
000000D0: 65 20 6F 66 20 74 68 65 20 70 72 6F 67 72 61 6D |e of the program|
000000E0: 20 77 68 65 72 65 20 20 22 76 61 6C 75 65 22 20 | where "value" |
000000F0: 20 69 73 20 0D 0D 20 20 20 20 20 20 20 20 64 65 | is .. de|
00000100: 66 69 6E 65 64 20 61 73 20 61 20 74 6F 74 61 6C |fined as a total|
00000110: 20 6F 66 20 36 34 20 65 6C 65 6D 65 6E 74 73 2E | of 64 elements.|
00000120: 0D 0D 20 20 20 20 20 20 20 20 20 20 20 20 54 6F |.. To|
00000130: 20 75 73 65 20 65 69 74 68 65 72 20 6F 66 20 74 | use either of t|
00000140: 68 65 20 74 77 6F 20 76 61 72 69 61 62 6C 65 73 |he two variables|
00000150: 20 69 6E 20 61 20 70 72 6F 67 72 61 6D 2C 20 77 | in a program, w|
00000160: 65 20 6D 75 73 74 20 0D 0D 20 20 20 20 20 20 20 |e must .. |
00000170: 20 61 64 64 20 20 74 77 6F 20 73 75 62 73 63 72 | add two subscr|
00000180: 69 70 74 73 20 74 6F 20 74 68 65 20 76 61 72 69 |ipts to the vari|
00000190: 61 62 6C 65 20 6E 61 6D 65 20 74 6F 20 74 65 6C |able name to tel|
000001A0: 6C 20 74 68 65 20 70 72 6F 67 72 61 6D 20 0D 0D |l the program ..|
000001B0: 20 20 20 20 20 20 20 20 77 68 69 63 68 20 20 65 | which e|
000001C0: 6C 65 6D 65 6E 74 20 6F 66 20 74 68 65 20 36 34 |lement of the 64|
000001D0: 20 77 65 20 64 65 73 69 72 65 20 74 6F 20 20 75 | we desire to u|
000001E0: 73 65 2E 20 20 20 45 78 61 6D 69 6E 69 6E 67 20 |se. Examining |
000001F0: 20 74 68 65 20 0D 0D 20 20 20 20 20 20 20 20 70 | the .. p|
00000200: 72 6F 67 72 61 6D 20 77 69 6C 6C 20 72 65 76 65 |rogram will reve|
00000210: 61 6C 20 74 77 6F 20 6C 6F 6F 70 73 2C 20 20 6F |al two loops, o|
00000220: 6E 65 20 6E 65 73 74 65 64 20 77 69 74 68 69 6E |ne nested within|
00000230: 20 74 68 65 20 6F 74 68 65 72 2C 20 0D 0D 20 20 | the other, .. |
00000240: 20 20 20 20 20 20 61 6E 64 20 62 6F 74 68 20 72 | and both r|
00000250: 61 6E 67 69 6E 67 20 69 6E 20 76 61 6C 75 65 20 |anging in value |
00000260: 66 72 6F 6D 20 31 20 74 6F 20 38 2E 20 20 54 68 |from 1 to 8. Th|
00000270: 65 20 74 77 6F 20 6C 6F 6F 70 20 69 6E 64 69 63 |e two loop indic|
00000280: 65 73 20 0D 0D 20 20 20 20 20 20 20 20 63 61 6E |es .. can|
00000290: 20 20 74 68 65 72 65 66 6F 72 65 20 20 62 65 20 | therefore be |
000002A0: 75 73 65 64 20 61 73 20 73 75 62 73 63 72 69 70 |used as subscrip|
000002B0: 74 73 20 6F 66 20 74 68 65 20 20 64 65 66 69 6E |ts of the defin|
000002C0: 65 64 20 20 61 72 72 61 79 20 0D 0D 20 20 20 20 |ed array .. |
000002D0: 20 20 20 20 76 61 72 69 61 62 6C 65 73 2E 20 20 | variables. |
000002E0: 20 54 68 65 20 20 76 61 72 69 61 62 6C 65 20 22 | The variable "|
000002F0: 63 68 65 63 6B 65 72 62 6F 61 72 64 22 20 69 73 |checkerboard" is|
00000300: 20 73 75 62 73 63 72 69 70 74 65 64 20 20 62 79 | subscripted by|
00000310: 20 0D 0D 20 20 20 20 20 20 20 20 62 6F 74 68 20 | .. both |
00000320: 20 6F 66 20 20 74 68 65 20 6C 6F 6F 70 20 69 6E | of the loop in|
00000330: 64 69 63 65 73 20 61 6E 64 20 65 61 63 68 20 6F |dices and each o|
00000340: 66 20 74 68 65 20 36 34 20 20 76 61 72 69 61 62 |f the 64 variab|
00000350: 6C 65 73 20 20 69 73 20 0D 0D 20 20 20 20 20 20 |les is .. |
00000360: 20 20 61 73 73 69 67 6E 65 64 20 61 20 76 61 6C | assigned a val|
00000370: 75 65 20 61 73 20 61 20 66 75 6E 63 74 69 6F 6E |ue as a function|
00000380: 20 6F 66 20 74 68 65 20 69 6E 64 69 63 65 73 2E | of the indices.|
00000390: 20 20 54 68 65 20 61 73 73 69 67 6E 65 64 20 0D | The assigned .|
000003A0: 0D 20 20 20 20 20 20 20 20 76 61 6C 75 65 20 20 |. value |
000003B0: 68 61 73 20 20 6E 6F 20 72 65 61 6C 20 6D 65 61 |has no real mea|
000003C0: 6E 69 6E 67 20 6F 74 68 65 72 20 74 68 61 6E 20 |ning other than |
000003D0: 74 6F 20 69 6C 6C 75 73 74 72 61 74 65 20 74 6F |to illustrate to|
000003E0: 20 20 79 6F 75 20 0D 0D 20 20 20 20 20 20 20 20 | you .. |
000003F0: 68 6F 77 20 20 69 74 20 69 73 20 64 6F 6E 65 2E |how it is done.|
00000400: 20 20 20 53 69 6E 63 65 20 74 68 65 20 76 61 6C | Since the val|
00000410: 75 65 20 6F 66 20 22 63 68 65 63 6B 65 72 62 6F |ue of "checkerbo|
00000420: 61 72 64 22 20 69 73 20 20 6E 6F 77 20 0D 0D 20 |ard" is now .. |
00000430: 20 20 20 20 20 20 20 61 76 61 69 6C 61 62 6C 65 | available|
00000440: 2C 20 20 69 74 20 69 73 20 75 73 65 64 20 74 6F |, it is used to|
00000450: 20 64 65 66 69 6E 65 20 73 6F 6D 65 20 76 61 6C | define some val|
00000460: 75 65 73 20 74 6F 20 62 65 20 75 73 65 64 20 20 |ues to be used |
00000470: 66 6F 72 20 0D 0D 20 20 20 20 20 20 20 20 74 68 |for .. th|
00000480: 65 20 76 61 72 69 61 62 6C 65 20 22 76 61 6C 75 |e variable "valu|
00000490: 65 22 2E 0D 0D |e"... |
.....@.....0....................
SAME MANNER AS A REAL CHECKER BOARD,
AN 8 BY 8 MATRIX. .. ANOTHER
WAY TO ACHIEVE THE SAME END IS TO DEFIN
E THE DOUBLE .. ARRAY AS IN THE
NEXT LINE OF THE PROGRAM WHERE "VALUE"
IS .. DEFINED AS A TOTAL OF 64 E
LEMENTS... TO USE EITHER OF T
HE TWO VARIABLES IN A PROGRAM, WE MUST .
. ADD TWO SUBSCRIPTS TO THE VARI
ABLE NAME TO TELL THE PROGRAM ..
WHICH ELEMENT OF THE 64 WE DESIRE TO U
SE. EXAMINING THE .. PROGRAM W
ILL REVEAL TWO LOOPS, ONE NESTED WITHIN
THE OTHER, .. AND BOTH RANGING I
N VALUE FROM 1 TO 8. THE TWO LOOP INDIC
ES .. CAN THEREFORE BE USED AS
SUBSCRIPTS OF THE DEFINED ARRAY ..
VARIABLES. THE VARIABLE "CHECKERB
OARD" IS SUBSCRIPTED BY .. BOTH
OF THE LOOP INDICES AND EACH OF THE 64
VARIABLES IS .. ASSIGNED A VAL
UE AS A FUNCTION OF THE INDICES. THE AS
SIGNED .. VALUE HAS NO REAL MEA
NING OTHER THAN TO ILLUSTRATE TO YOU ..
HOW IT IS DONE. SINCE THE VAL
UE OF "CHECKERBOARD" IS NOW .. A
VAILABLE, IT IS USED TO DEFINE SOME VAL
UES TO BE USED FOR .. THE VARIAB
LE "VALUE"...
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