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|00000d80| 74 20 77 6f 72 6b 2e 20 | 53 6f 20 74 68 65 72 65 |t work. |So there|
|00000d90| 20 69 73 20 3d 0a 61 6e | 20 61 6d 62 69 67 75 69 | is =.an| ambigui|
|00000da0| 74 79 20 69 6e 20 50 61 | 73 63 61 6c 20 74 68 61 |ty in Pa|scal tha|
|00000db0| 74 20 64 6f 6e 27 74 20 | 65 78 69 73 74 20 69 6e |t don't |exist in|
|00000dc0| 20 43 2e 0a 0a 53 6f 6d | 65 20 6f 70 65 72 61 74 | C...Som|e operat|
|00000dd0| 6f 72 73 0a 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |ors.====|========|
|00000de0| 3d 3d 0a 46 69 72 73 74 | 2c 20 64 6f 6e 27 74 20 |==.First|, don't |
|00000df0| 66 6f 72 67 65 74 3a 0a | 7b 50 61 73 63 61 6c 7d |forget:.|{Pascal}|
|00000e00| 20 61 20 3a 3d 20 62 3b | 20 2d 3e 20 61 20 3d 20 | a := b;| -> a = |
|00000e10| 62 3b 0a 7b 50 61 73 63 | 61 6c 7d 20 61 20 3d 20 |b;.{Pasc|al} a = |
|00000e20| 62 3b 20 2d 3e 20 61 20 | 3d 3d 20 62 3b 0a 7b 50 |b; -> a |== b;.{P|
|00000e30| 61 73 63 61 6c 7d 20 61 | 20 3c 3e 20 62 3b 20 2d |ascal} a| <> b; -|
|00000e40| 3e 20 61 20 21 3d 20 62 | 3b 0a 0a 59 6f 75 20 63 |> a != b|;..You c|
|00000e50| 61 6e 20 77 72 69 74 65 | 3a 0a 61 20 3d 20 62 3b |an write|:.a = b;|
|00000e60| 0a 61 20 2b 3d 20 62 3b | 20 3c 3d 3e 20 61 20 3d |.a += b;| <=> a =|
|00000e70| 20 61 20 2b 20 62 3b 0a | 61 20 2d 3d 20 62 3b 20 | a + b;.|a -= b; |
|00000e80| 3c 3d 3e 20 61 20 3d 20 | 61 20 2d 20 62 3b 0a 61 |<=> a = |a - b;.a|
|00000e90| 20 2a 3d 20 62 3b 20 3c | 3d 3e 20 61 20 3d 20 61 | *= b; <|=> a = a|
|00000ea0| 20 2a 20 62 3b 0a 61 20 | 2f 3d 20 62 3b 20 3c 3d | * b;.a |/= b; <=|
|00000eb0| 3e 20 61 20 3d 20 61 20 | 2f 20 62 3b 20 2f 2a 20 |> a = a |/ b; /* |
|00000ec0| 66 6f 72 20 66 6c 6f 61 | 74 20 28 50 61 73 63 61 |for floa|t (Pasca|
|00000ed0| 6c 20 2f 29 20 61 6e 64 | 20 69 6e 74 65 67 65 72 |l /) and| integer|
|00000ee0| 20 28 50 61 73 63 61 6c | 20 44 49 56 29 20 2a 2f | (Pascal| DIV) */|
|00000ef0| 0a 61 20 25 3d 20 62 3b | 20 3c 3d 3e 20 61 20 3d |.a %= b;| <=> a =|
|00000f00| 20 61 20 25 20 62 3b 20 | 2f 2a 20 4d 4f 44 20 2a | a % b; |/* MOD *|
|00000f10| 2f 0a 61 20 26 3d 20 62 | 3b 20 3c 3d 3e 20 61 20 |/.a &= b|; <=> a |
|00000f20| 3d 20 61 20 26 20 62 3b | 20 2f 2a 20 62 69 74 2d |= a & b;| /* bit-|
|00000f30| 77 69 73 65 20 2a 2f 0a | 61 20 7c 3d 20 62 3b 20 |wise */.|a |= b; |
|00000f40| 3c 3d 3e 20 61 20 3d 20 | 61 20 7c 20 62 3b 20 2f |<=> a = |a | b; /|
|00000f50| 2a 20 62 69 74 2d 77 69 | 73 65 20 2a 2f 0a 61 20 |* bit-wi|se */.a |
|00000f60| 5e 3d 20 62 3b 20 3c 3d | 3e 20 61 20 3d 20 61 20 |^= b; <=|> a = a |
|00000f70| 5e 20 62 3b 20 2f 2a 20 | 62 69 74 2d 77 69 73 65 |^ b; /* |bit-wise|
|00000f80| 20 2a 2f 0a 2b 2b 61 3b | 20 3c 3d 3e 20 61 20 2b | */.++a;| <=> a +|
|00000f90| 3d 20 31 3b 20 3c 3d 3e | 20 61 20 3d 20 61 20 2b |= 1; <=>| a = a +|
|00000fa0| 20 31 3b 0a 2d 2d 61 3b | 20 3c 3d 3e 20 61 20 2d | 1;.--a;| <=> a -|
|00000fb0| 3d 20 31 3b 20 3c 3d 3e | 20 61 20 3d 20 61 20 2d |= 1; <=>| a = a -|
|00000fc0| 20 31 3b 0a 0a 77 68 65 | 72 65 20 61 20 69 73 20 | 1;..whe|re a is |
|00000fd0| 61 20 6c 65 66 74 2d 76 | 61 6c 75 65 20 28 73 6f |a left-v|alue (so|
|00000fe0| 6d 65 74 68 69 6e 67 20 | 74 68 61 74 20 63 61 6e |mething |that can|
|00000ff0| 20 62 65 20 61 73 73 69 | 67 6e 65 64 29 20 61 6e | be assi|gned) an|
|00001000| 64 20 62 20 61 20 76 61 | 6c 75 65 0a 41 20 6c 65 |d b a va|lue.A le|
|00001010| 66 74 2d 76 61 6c 75 65 | 20 69 73 3a 0a 2d 20 61 |ft-value| is:.- a|
|00001020| 20 76 61 72 69 61 62 6c | 65 2c 20 6d 65 6d 62 65 | variabl|e, membe|
|00001030| 72 20 6f 66 20 73 74 72 | 75 63 74 20 28 52 45 43 |r of str|uct (REC|
|00001040| 4f 52 44 29 2c 20 75 6e | 69 6f 6e 20 28 52 45 43 |ORD), un|ion (REC|
|00001050| 4f 52 44 20 43 41 53 45 | 20 4f 46 29 2c 20 61 72 |ORD CASE| OF), ar|
|00001060| 72 61 79 2e 2e 2e 0a 2d | 20 2a 61 64 64 72 2c 20 |ray....-| *addr, |
|00001070| 77 68 65 72 65 20 61 64 | 64 72 20 69 73 20 61 20 |where ad|dr is a |
|00001080| 76 61 6c 75 65 0a 0a 41 | 4c 4c 20 6f 66 20 74 68 |value..A|LL of th|
|00001090| 65 6d 20 72 65 74 75 72 | 6e 20 74 68 65 20 76 61 |em retur|n the va|
|000010a0| 6c 75 65 20 6f 66 20 27 | 61 27 20 61 66 74 65 72 |lue of '|a' after|
|000010b0| 20 74 68 65 20 63 6f 6d | 70 75 74 61 74 69 6f 6e | the com|putation|
|000010c0| 20 65 78 63 65 70 74 20 | 61 2b 2b 20 61 6e 64 20 | except |a++ and |
|000010d0| 61 2d 2d 20 77 68 69 63 | 68 20 72 65 74 75 72 6e |a-- whic|h return|
|000010e0| 20 74 68 65 20 76 61 6c | 75 65 20 62 65 66 6f 72 | the val|ue befor|
|000010f0| 65 20 74 68 65 20 69 6e | 63 72 65 6d 65 6e 74 61 |e the in|crementa|
|00001100| 74 69 6f 6e 2f 64 65 63 | 72 65 6d 3d 0a 65 6e 74 |tion/dec|rem=.ent|
|00001110| 61 74 69 6f 6e 2e 0a 0a | 46 75 6e 63 74 69 6f 6e |ation...|Function|
|00001120| 73 20 61 6e 64 20 50 72 | 6f 63 65 64 75 72 65 73 |s and Pr|ocedures|
|00001130| 0a 3d 3d 3d 3d 3d 3d 3d | 3d 3d 3d 3d 3d 3d 3d 3d |.=======|========|
|00001140| 3d 3d 3d 3d 3d 3d 3d 3d | 3d 0a 54 68 65 72 65 20 |========|=.There |
|00001150| 69 73 20 6e 6f 20 64 69 | 66 66 65 72 65 6e 63 65 |is no di|fference|
|00001160| 20 62 65 74 77 65 65 6e | 20 66 75 6e 63 74 69 6f | between| functio|
|00001170| 6e 73 20 61 6e 64 20 70 | 72 6f 63 65 64 75 72 65 |ns and p|rocedure|
|00001180| 73 3a 0a 0a 41 20 70 72 | 6f 63 65 64 75 72 65 20 |s:..A pr|ocedure |
|00001190| 69 73 20 61 20 66 75 6e | 63 74 69 6f 6e 20 74 68 |is a fun|ction th|
|000011a0| 61 74 20 72 65 74 75 72 | 6e 20 76 6f 69 64 20 28 |at retur|n void (|
|000011b0| 76 6f 69 64 20 6d 65 61 | 6e 20 6e 6f 74 68 69 6e |void mea|n nothin|
|000011c0| 67 29 3b 20 61 20 73 74 | 61 74 65 6d 65 6e 74 20 |g); a st|atement |
|000011d0| 69 73 20 73 69 6d 70 6c | 79 20 61 20 65 78 70 72 |is simpl|y a expr|
|000011e0| 65 73 73 69 6f 6e 2e 20 | 54 68 65 73 65 20 61 72 |ession. |These ar|
|000011f0| 65 20 6c 65 67 61 6c 3a | 0a 33 3b 20 34 2b 35 3b |e legal:|.3; 4+5;|
|00001200| 20 61 2b 62 2b 35 3b 20 | 2f 2a 20 67 69 76 65 6e | a+b+5; |/* given|
|00001210| 20 61 20 61 6e 64 20 62 | 20 61 72 65 20 64 65 66 | a and b| are def|
|00001220| 69 6e 65 64 20 2a 2f 0a | 61 20 3d 20 62 20 3d 20 |ined */.|a = b = |
|00001230| 33 3b 20 3c 3d 3e 20 61 | 20 3d 20 28 62 20 3d 20 |3; <=> a| = (b = |
|00001240| 33 29 3b 20 3c 3d 3e 20 | 62 20 3d 20 33 3b 20 61 |3); <=> |b = 3; a|
|00001250| 20 3d 20 62 3b 0a 0a 63 | 68 61 72 20 20 20 20 52 | = b;..c|har    R|
|00001260| 65 61 64 4b 65 79 20 28 | 76 6f 69 64 29 3b 0a 63 |eadKey (|void);.c|
|00001270| 68 61 72 20 20 20 20 52 | 65 61 64 4b 65 79 20 28 |har    R|eadKey (|
|00001280| 29 0a 7b 0a 20 20 20 20 | 63 68 61 72 20 6b 65 79 |).{.    |char key|
|00001290| 3b 0a 20 20 20 20 2e 2e | 2e 2e 2e 2e 0a 20 20 20 |;.    ..|.....   |
|000012a0| 20 72 65 74 75 72 6e 20 | 6b 65 79 3b 0a 7d 0a 0a | return |key;.}..|
|000012b0| 63 68 61 72 20 63 3b 0a | 0a 63 20 3d 20 52 65 61 |char c;.|.c = Rea|
|000012c0| 64 4b 65 79 20 28 29 3b | 20 2f 2a 20 74 68 65 20 |dKey ();| /* the |
|000012d0| 72 65 74 75 72 6e 20 76 | 61 6c 75 65 20 69 73 20 |return v|alue is |
|000012e0| 75 73 65 64 20 2a 2f 0a | 52 65 61 64 4b 65 79 20 |used */.|ReadKey |
|000012f0| 28 29 3b 20 2f 2a 20 74 | 68 69 73 20 69 73 20 6c |(); /* t|his is l|
|00001300| 65 67 61 6c 3a 20 74 68 | 65 20 72 65 74 75 72 6e |egal: th|e return|
|00001310| 20 76 61 6c 75 65 20 69 | 73 20 6e 6f 74 20 75 73 | value i|s not us|
|00001320| 65 64 20 2a 2f 0a 0a 4e | 6f 74 65 0a 3d 3d 3d 3d |ed */..N|ote.====|
|00001330| 0a 49 20 68 61 76 65 20 | 77 72 6f 74 65 20 68 65 |.I have |wrote he|
|00001340| 72 65 20 73 6f 6d 65 20 | 65 78 70 6c 61 6e 61 74 |re some |explanat|
|00001350| 69 6f 6e 73 20 61 62 6f | 75 74 20 77 68 61 74 20 |ions abo|ut what |
|00001360| 73 65 65 6d 20 74 6f 20 | 62 65 20 69 6d 70 6f 72 |seem to |be impor|
|00001370| 74 61 6e 74 20 66 6f 72 | 20 74 68 65 20 43 20 62 |tant for| the C b|
|00001380| 65 67 69 6e 6e 65 72 3b | 20 49 20 68 61 76 65 20 |eginner;| I have |
|00001390| 66 6f 72 67 6f 74 74 65 | 6e 20 6c 6f 74 73 20 6f |forgotte|n lots o|
|000013a0| 66 20 74 68 69 6e 67 73 | 2e 0a 0a 56 61 6c 65 6e |f things|...Valen|
|000013b0| 74 69 6e 20 42 6f 6e 6e | 61 72 64 0a 62 6f 6e 6e |tin Bonn|ard.bonn|
|000013c0| 61 72 64 76 40 70 72 61 | 74 69 71 75 65 2e 66 72 |ardv@pra|tique.fr|
|000013d0| 0a 7f 0a 0a             |                         |....    |        |
+--------+-------------------------+-------------------------+--------+--------+