0. #include1. #include 2. #include 3. #include 4. 5. #define BELL '\a'6. #define DEALER 07. #define PLAYER 18. 9. #define ACELOW 010. #define ACEHIGH 111. 12. int askedForName = 0;13. 14. 15. void dispTitle(void);16. void initCardsScreen(int cards[52],int playerPoints[2],17. int dealerPoints[2], int total[2], 18. int *numCards);19. int dealCard(int * numCards,int cards[52]);20. void dispCard(int cardDrawn,int points[2]);21. void totalIt(int points[2],int tatal[2],int who);22. void dealerGetsCard(int *numCards,int cards[52],23. int dealerPoints[2]);24. void playerGetsCard(int *numCards,int cards[52],25. int playerPoints[2]);26. char getAns(char mesg[]);27. void findWinner(int total[2]);28. 29. main()30. {31. int numCards;32. int cards[52],playerPoints[2],dealerPoints[2],total[2];33. char ans;34. 35. do 36. { 37. initCardsScreen(cards,playerPoints,dealerPoints,total, &numCards);38. dealerGetsCard(&numCards,cards, dealerPoints);39. printf("\n");40. playerGetsCard(&numCards,cards,playerPoints); 41. playerGetsCard(&numCards,cards,playerPoints);42. do43. {44. ans = getAns("Hit or stand (H/S)?");45. if ( ans == 'H' )46. { 47. playerGetsCard(&numCards,cards,playerPoints);48. } 49. }50. while( ans != 'S' );51. 52. totalIt(playerPoints,total,PLAYER);53. do54. {55. dealerGetsCard(&numCards,cards,dealerPoints);56. }57. while (dealerPoints[ACEHIGH] < 17 );58. 59. totalIt(dealerPoints,total,DEALER);60. findWinner(total); 61. 62. ans = getAns("\nPlay again(Y/N)?"); 63. }64. while(ans=='Y');65. 66. return 0;67. }68. 69. void initCardsScreen( int cards[52],int playerPoints[2],70. int dealerPoints[2], int total[2], 71. int *numCards )72. {73. int sub,val = 1 ;74. char firstName[15];75. *numCards=52;76. 77. for(sub=0;sub<=51;sub++)78. {79. val = (val == 14) ? 1 : val;80. cards[sub] = val;81. val++; 82. }83. 84. for(sub=0;sub<=1;sub++)85. { 86. playerPoints[sub]=dealerPoints[sub]=total[sub]=0;87. }88. dispTitle();89. 90. if (askedForName==0)91. { 92. printf("What is your first name?");93. scanf(" %s",firstName);94. askedForName=1;95. printf("Ok, %s,get ready for casino action!\n\n",firstName);96. getchar();97. }98. return; 99. }100. 101. void playerGetsCard(int *numCards,int cards[52],int playerPoints[2])102. {103. int newCard;104. newCard = dealCard(numCards, cards);105. printf("You draw:");106. dispCard(newCard,playerPoints);107. }108. 109. 110. void dealerGetsCard(int *numCards,int cards[52],int dealerPoints[2])111. {112. int newCard;113. newCard = dealCard(numCards,cards);114. printf("The dealer draws:");115. dispCard(newCard,dealerPoints);116. }117. 118. int dealCard(int * numCards,int cards[52])119. {120. int cardDrawn,subDraw;121. time_t t;122. srand(time(&t));123. subDraw = (rand()%(*numCards));124. cardDrawn = cards[subDraw];125. cards[subDraw] = cards[*numCards -1];126. (*numCards)--;127. return cardDrawn;128. }129. 130. void dispCard(int cardDrawn, int points[2])131. {132. switch(cardDrawn)133. {134. case(11): printf("%s\n","Jack");135. points[ACELOW] += 10;136. points[ACEHIGH] += 10;137. break;138. case(12): printf("%s\n","Queen");139. points[ACELOW] += 10;140. points[ACEHIGH] += 10;141. break;142. case(13): printf("%s\n","King");143. points[ACELOW] += 10;144. points[ACEHIGH] += 10;145. break;146. default : points[ACELOW] += cardDrawn;147. if(cardDrawn==1)148. { 149. printf("%s\n","Ace");150. points[ACEHIGH]+= 11;151. }152. else153. { 154. points[ACEHIGH]+=cardDrawn;155. printf("%d\n",cardDrawn); 156. }157. }158. return ;159. }160. 161. void totalIt(int points[2],int total[2],int who)162. {163. if ( (points[ACELOW] == points[ACEHIGH])164. ||(points[ACEHIGH] < 21 ))165. { 166. total[who] = points[ACELOW];167. }168. else169. { 170. total[who] = points[ACEHIGH];171. }172. 173. if (who == PLAYER )174. {175. printf("You have a total of %d\n\n", total[PLAYER]);176. }177. else178. {179. printf("The house stands with a total of %d\n\n", 180. total[DEALER]);181. }182. return;183. }184. 185. void findWinner(int total[2])186. {187. if ( total[DEALER] == 21 )188. {189. printf("The house wins.\n");190. return ;191. }192. if ( (total[DEALER] > 21) && (total[PLAYER] > 21) )193. { 194. printf("%s", "Nobody wins.\n");195. return ; 196. }197. if ((total[DEALER] >= total[PLAYER])&& (total[DEALER] < 21))198. { 199. printf("The house wins.\n");200. return ; 201. }202. printf("%s%c","You win!\n",BELL);203. return;204. }205. 206. char getAns(char mesg[])207. {208. char ans;209. printf("%s", mesg);210. ans = getchar();211. getchar();212. return toupper(ans);213. }214. 215. void dispTitle(void)216. {217. int i = 0 ;218. while(i<25)219. { 220. printf("\n");221. i++; 222. }223. printf("\n\n*Step right up to the Blackjack tables*\n\n");224. return ;225. }
main()函数中player完成抽牌之后，立刻计算了player的点数：
52. totalIt(playerPoints,total,PLAYER);
这个计算结果基于ACE的点数被作为1或11两种可能性，取最好一种作为最后的结果。
161. void totalIt(int points[2],int total[2],int who)162. {163. if ( (points[ACELOW] == points[ACEHIGH])164. ||(points[ACEHIGH] > 21 ))165. { 166. total[who] = points[ACELOW];167. }168. else169. { 170. total[who] = points[ACEHIGH];171. }172. 173. if (who == PLAYER )174. {175. printf("You have a total of %d\n\n", total[PLAYER]);176. }177. else178. {179. printf("The house stands with a total of %d\n\n", 180. total[DEALER]);181. }182. return;183. } 这个函数让我们得以领略什么叫思路含糊和废话连篇。首先
163. if ( (points[ACELOW] == points[ACEHIGH])164. ||(points[ACEHIGH] > 21 ))165. { 166. total[who] = points[ACELOW];167. }168. else169. { 170. total[who] = points[ACEHIGH];171. } 它的意思是当较高点数超过21点时把较低作为最终的点数，否则把较高点数作为最后的点数。显而易见这可以更简洁地表述为
if ( points[ACEHIGH] > 21 ) { total[who] = points[ACELOW]; } else { total[who] = points[ACEHIGH]; } 原来的代码把“(points[ACELOW] == points[ACEHIGH])||”写出来是思路不清导致的拖泥带水。
更简洁的写法是：
total[who] = ( points[ACEHIGH] > 21 )? points[ACELOW]: points[ACEHIGH];
“?:”这个三目运算在这里应用得恰到好处。
有些人对三目运算有一种无名的恐惧，鼓吹所谓“尽量不要用三目运算符”。这是毫无道理的，这种无理源自无知。他们自己不会用刀，于是就骗人骗己地宣称使用木棍强于用刀。
173. if (who == PLAYER )174. {175. printf("You have a total of %d\n\n", total[PLAYER]);176. }177. else178. {179. printf("The house stands with a total of %d\n\n", 180. total[DEALER]);181. } 这一段同样拖泥带水，其实它的效果和下面写法没有本质区别：
printf( "%s a total of %d\n\n", who == PLAYER ? "You have" : "The house stands with", total[who] );
所以totalIt()函数应改写为
void totalIt(int [],int [],int ); void totalIt(int points[],int total[],int who) { total[who] = ( points[ACEHIGH] > 21 )? points[ACELOW]: points[ACEHIGH]; printf( "%s a total of %d\n\n", who == PLAYER ? "You have" : "The house stands with", total[who] ); } 计算了完player的点数之后，按照规则在main()中由dealer继续抽牌（前面已抽过第一张牌）。dealer抽牌的策略是不到17点则继续，据代码作者说现实中的庄家的策略也是如此。
53. do54. {55. dealerGetsCard(&numCards,cards,dealerPoints);56. }57. while ( dealerPoints[ACEHIGH] < 17 ); dealerGetsCard ()函数的功能与playerGetsCard()函数重叠，前面已经提到过，甚至可以说这两个函数都是多余的。
此外这里还有一个更严重的问题，那就是“dealerPoints[ACEHIGH] < 17”这个表达式的逻辑问题。这个表达式要求dealer的点数达到17点或以上时停止抽牌，但问题在于点数有两种计算方法，一种是把Ace作为11点（Soft hand），另一种是把Ace作为1点。“dealerPoints[ACEHIGH] ”的意义是Soft hand点数，但是原作者在对程序的说明中压根就没有明确dealer的Soft hand点数达到或超过17点时停牌，只是泛泛地说了一句“the dealer stands on 17”。按软件工程的说法，这叫需求不清，是比代码错误更加严重的错误。
紧接着，矛盾出现了。
59. totalIt(dealerPoints,total,DEALER);
totalIt()函数计算dealer的点数却是按照最好成绩计算的，这就发生了矛盾。比如dealer为15点时又取了一张牌Ace，按照Soft hand规则，dealer的点数是25点，但最后的成绩却是按照硬牌规则为16点，而如果dealer的点数为16点，那么前面他根本就不应该停牌。这是“双重标准”的C语言版。
这里较为合理的写法应该是
do { dealerGetsCard(&numCards,cards,dealerPoints); totalIt(dealerPoints,total,DEALER); } while ( total [DEALER] < 17 );