{"id":1178,"date":"2024-04-08T09:04:11","date_gmt":"2024-04-08T01:04:11","guid":{"rendered":"http:\/\/www.jusesgod.com\/?p=1178"},"modified":"2024-09-10T15:40:23","modified_gmt":"2024-09-10T07:40:23","slug":"%e7%ac%ac2%e7%ab%a0-%e4%bf%a1%e6%81%af%e7%9a%84%e8%a1%a8%e7%a4%ba%e5%92%8c%e5%a4%84%e7%90%86","status":"publish","type":"post","link":"http:\/\/www.jusesgod.com\/?p=1178","title":{"rendered":"\u7b2c2\u7ae0 \u4fe1\u606f\u7684\u8868\u793a\u548c\u5904\u7406"},"content":{"rendered":"\n

\u73b0\u4ee3\u8ba1\u7b97\u673a\u5b58\u50a8\u548c\u5904\u7406\u7684\u4fe1\u606f\u4ee5\u4e8c\u503c\u4fe1\u53f7\u8868\u793a\uff0c\u79f0\u4e3a\u4f4d<\/strong><\/em>(bit)<\/em><\/strong>\u3002\u5c06\u4f4d\u7ec4\u5408\u5728\u4e00\u8d77\uff0c\u518d\u52a0\u4e0a\u67d0\u79cd\u89e3\u91ca(interpretation)<\/em><\/strong>\uff0c\u6211\u4eec\u5c31\u80fd\u591f\u8868\u793a\u4efb\u4f55\u6709\u9650\u96c6\u5408\u7684\u5143\u7d20\u3002\u4f8b\u5982\uff1a\u65e0\u7b26\u53f7(unsigned)<\/em><\/strong>\u3001\u8865\u7801(two`s-complement)<\/em><\/strong>\u3001\u6d6e\u70b9\u6570(floating-point)<\/em><\/strong>\u3002\u8ba1\u7b97\u673a\u8868\u793a\u6cd5\u662f\u7528\u6709\u9650\u6570\u91cf\u7684\u4f4d\u6765\u5bf9\u4e00\u4e2a\u6570\u5b57\u7f16\u7801\uff0c\u56e0\u6b64\uff0c\u7ed3\u679c\u592a\u5927\u4ee5\u81f4\u4e0d\u80fd\u8868\u793a\u65f6\uff0c\u67d0\u4e9b\u8fd0\u7b97\u5c31\u4f1a\u6ea2\u51fa(overflow)<\/em><\/strong>\u3002\u6ea2\u51fa\u4f1a\u5bfc\u81f4\u67d0\u4e9b\u4ee4\u4eba\u5403\u60ca\u7684\u540e\u679c<\/em>\u3002<\/p>\n\n\n\n

2.1 \u4fe1\u606f\u5b58\u50a8<\/h2>\n\n\n\n

\u5927\u591a\u6570\u8ba1\u7b97\u673a\u90fd\u4f7f\u75288\u4f4d\u7684\u5757\u6216\u8005\u5b57\u8282\uff08byte\uff09<\/strong><\/em>\u4f5c\u4e3a\u6700\u5c0f\u7684\u53ef\u5bfb\u5740\u5b58\u50a8\u5355\u4f4d\u3002
\u50a8\u5b58\u5668\u7684\u6bcf\u4e2a\u5b57\u8282\u90fd\u6709\u552f\u4e00\u7684\u4e00\u4e2a\u6570\u5b57\u6765\u8868\u793a\uff0c\u79f0\u4e3a\u5730\u5740\uff08address\uff09<\/em><\/strong>\u3002
\u6240\u6709\u5730\u5740\u96c6\u5408\u79f0\u4e3a\u865a\u62df\u5b58\u50a8\u5668\uff08virtual address space\uff09<\/em><\/strong>\uff0c\u5b9e\u9645\u7684\u5b9e\u73b0\u662f\u968f\u673a\u8bbf\u95ee\u5b58\u50a8\u5668\uff08RAM\uff09<\/em><\/strong>\u3001\u78c1\u76d8\u5b58\u50a8\u5668\u3001\u7279\u6b8a\u786c\u4ef6\u559d\u64cd\u4f5c\u7cfb\u7edf\u8f6f\u4ef6\u7ed3\u5408\u8d77\u6765\uff0c\u4e3a\u7a0b\u5e8f\u63d0\u4f9b\u7684\u4e00\u4e2a\u770b\u4e0a\u53bb\u7edf\u4e00\u7684\u5b57\u8282\u6570\u7ec4\u3002<\/p>\n\n\n\n

2.1.1 \u5341\u516d\u8fdb\u5236\u8868\u793a\u6cd5<\/h3>\n\n\n\n

\u5982\u679c\u4ee516\u4e3a\u57fa\u6570\u8868\u793a\u6570\u5b57\u7684\u65b9\u6cd5\u53eb\u505a\u5341\u516d\u8fdb\u5236\u6cd5\uff08hexadecimal\uff09<\/em><\/strong>\u7b80\u5199\u4e3a\uff08hex\uff09\u3002
\u4e00\u4e2a\u5b57\u8282\u7684\u4e8c\u8fdb\u5236\u8868\u793a 000000002<\/sub> ~ 111111112<\/sub>\uff1b\u56db\u4e2a\u4e8c\u8fdb\u5236\u4f4d\u53ef\u4ee5\u7f29\u51cf\u6210\u4e00\u4e2a\u5341\u516d\u8fdb\u5236\u4f4d\uff0c\u8fd9\u6837\u4e00\u4e2a\u5b57\u8282\u5c31\u80fd\u8868\u793a\u62100016<\/sub>~FF16<\/sub>\u3002C\u8bed\u8a00\u4e2d\u4ee50x\u62160X\u5f00\u5934\u7684\u6570\u5b57\u5e38\u91cf\u88ab\u8ba4\u4e3a\u662f\u5341\u516d\u8fdb\u5236\u7684\u6570\u503c\u3002<\/p>\n\n\n\n

\u5341\u516d\u8fdb\u5236\u6570<\/td>0<\/td>1<\/td>2<\/td>3<\/td>4<\/td>5<\/td>6<\/td>7<\/td><\/tr>
\u5341\u8fdb\u5236\u6570<\/td>0<\/td>1<\/td>2<\/td>3<\/td>4<\/td>5<\/td>6<\/td>7<\/td><\/tr>
\u4e8c\u8fdb\u5236\u6570<\/td>0000<\/td>0001<\/td>0010<\/td>0011<\/td>0100<\/td>0101<\/td>0110<\/td>0111<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\u5341\u516d\u8fdb\u5236\u6570<\/td>8<\/td>9<\/td>10<\/td>11<\/td>12<\/td>13<\/td>14<\/td>15<\/td><\/tr>
\u5341\u8fdb\u5236\u6570<\/td>8<\/td>9<\/td>10<\/td>11<\/td>12<\/td>13<\/td>14<\/td>15<\/td><\/tr>
\u4e8c\u8fdb\u5236\u6570<\/td>1000<\/td>1001<\/td>1010<\/td>1011<\/td>1100<\/td>1101<\/td>1110<\/td>1111<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

2.1.2 \u5b57<\/h3>\n\n\n\n

\u5b57\u957f\uff08word size\uff09\u6307\u660e\u6574\u6570\u548c\u6307\u9488\u6570\u636e\u7684\u6807\u79f0\u5927\u5c0f\uff08nominal size\uff09\u3002
\u5b57\u957f\u51b3\u5b9a\u7684\u6700\u91cd\u8981\u7684\u7cfb\u7edf\u53c2\u6570\u5c31\u662f\u865a\u62df\u5730\u5740\u7a7a\u95f4\u7684\u6700\u5927\u5927\u5c0f\u3002\u5bf9\u4e8e\u4e00\u4e2a\u5b57\u957f\u4e3aw\u4f4d\u7684\u673a\u5668\u800c\u8a00\uff0c\u865a\u62df\u5730\u5740\u8303\u56f4\u662f0~2w<\/sup>-1\u3002\u4eca\u5929\u5927\u591a\u6570\u8ba1\u7b97\u673a\u5b57\u957f\u90fd\u662f32\u4f4d\uff0c\u8fd9\u5c31\u9650\u5b9a\u4e86\u5730\u5740\u7a7a\u95f4\u4e3a4\u5343\u5146\u5b57\u8282\uff084GB\uff09\u3002<\/p>\n\n\n\n

2.1.3 \u6570\u636e\u5927\u5c0f<\/h3>\n\n\n\n
C\u58f0\u660e<\/td>32\u4f4d\u673a\u5668<\/td>64\u4f4d\u673a\u5668<\/td><\/tr>
char<\/td>1<\/td>1<\/td><\/tr>
short int<\/td>2<\/td>2<\/td><\/tr>
int<\/td>4<\/td>4<\/td><\/tr>
long int<\/td>4<\/td>8<\/mark><\/td><\/tr>
long long int<\/td>8<\/td>8<\/td><\/tr>
char *<\/td>4<\/td>8<\/mark><\/td><\/tr>
float<\/td>4<\/td>4<\/td><\/tr>
double<\/td>8<\/td>8<\/td><\/tr><\/tbody><\/table>
C\u8bed\u8a00\u4e2d\u6570\u5b57\u6570\u636e\u7c7b\u578b\u7684\u5b57\u8282\u6570<\/figcaption><\/figure>\n\n\n\n

2.1.4 \u5bfb\u5740\u548c\u5b57\u8282\u987a\u5e8f<\/h3>\n\n\n\n

\u6700\u4f4e\u6709\u6548\u5b57\u8282\u5728\u6700\u524d\u9762\u7684\u65b9\u5f0f\uff0c\u79f0\u4e3a\u5c0f\u7aef\u6cd5\uff08little endian\uff09\u3002
\u6700\u9ad8\u6709\u6548\u5b57\u8282\u5728\u6700\u524d\u9762\u7684\u65b9\u5f0f\uff0c\u79f0\u4e3a\u5927\u7aef\u6cd5\uff08big endian\uff09\u3002
\u5927\u591a\u6570IBM\u548cSun Microsystems\u7684\u673a\u5668\u90fd\u91c7\u7528\u8fd9\u79cd\u89c4\u5219\u3002
\u8bb8\u591a\u6bd4\u8f83\u65b0\u7684\u5fae\u5904\u7406\u5668\u4f7f\u7528\u53cc\u7aef\u6cd5\uff08bi-endian\uff09\uff0c\u4e5f\u5c31\u662f\u53ef\u4ee5\u628a\u5b83\u4eec\u914d\u7f6e\u6210\u4f5c\u4e3a\u5927\u7aef\u6216\u8005\u5c0f\u7aef\u7684\u673a\u5668\u8fd0\u884c\u3002<\/p>\n\n\n\n

2.1.5 \u8868\u793a\u5b57\u7b26\u4e32<\/h3>\n\n\n\n

C\u8bed\u8a00\u4e2d\u5b57\u7b26\u4e32\u88ab\u7f16\u7801\u4e3a\u4e00\u4e2a\u4ee5null\uff08\u503c\u4e3a0\uff09\u5b57\u7b26\u7ed3\u5c3e\u7684\u5b57\u7b26\u6570\u7ec4\u3002\u5e38\u7528ASCII\u5b57\u7b26\u7801\u3002
\u5728\u4f7f\u7528ASCII\u7f16\u7801\u4f5c\u4e3a\u5b57\u7b26\u7f16\u7801\u7684\u4efb\u4f55\u7cfb\u7edf\u4e0a\u90fd\u5c06\u5f97\u5230\u76f8\u540c\u7ed3\u679c\uff0c\u4e0e\u5b57\u8282\u987a\u5e8f\u548c\u5b57\u5927\u5c0f\u65e0\u5173\u3002\u56e0\u6b64\u6587\u672c\u6570\u636e\u6bd4\u4e8c\u8fdb\u5236\u6570\u636e\u5177\u6709\u66f4\u5f3a\u7684\u5e73\u53f0\u72ec\u7acb\u6027\u3002<\/p>\n\n\n\n

2.1.6 \u8868\u793a\u4ee3\u7801<\/h3>\n\n\n\n

\u4e0d\u540c\u673a\u5668\u6765\u884c\u4f7f\u7528\u4e0d\u540c\u7684\u6307\u4ee4\u548c\u7f16\u7801\u65b9\u5f0f\u3002\u6240\u4ee5\u4e00\u6837\u7684\u8fdb\u7a0b\u8fd0\u884c\u5728\u4e0d\u540c\u7684\u64cd\u4f5c\u7cfb\u7edf\u4e0a\u4e5f\u4f1a\u6709\u4e0d\u540c\u7684\u7f16\u7801\u89c4\u5219\u3002\u56e0\u6b64\u4e8c\u8fdb\u5236\u4ee3\u7801\u662f\u4e0d\u517c\u5bb9\u7684\u3002\u4e8c\u8fdb\u5236\u4ee3\u7801\u5f88\u5c11\u80fd\u5728\u4e0d\u540c\u673a\u5668\u548c\u64cd\u4f5c\u7cfb\u7edf\u4e2d\u7ec4\u5408\u4e4b\u95f4\u79fb\u690d\u3002<\/p>\n\n\n\n

2.1.7 \u5e03\u5c14\u4ee3\u6570\u7b80\u4ecb<\/h3>\n\n\n\n

\u5c06\u903b\u8f91\u503cTRUE\uff08\u771f\uff09\u548cFALSE\uff08\u5047\uff09\u7f16\u7801\u4e3a\u4e8c\u8fdb\u52361\u548c0\uff0c\u80fd\u591f\u8bbe\u8ba1\u51fa\u4e00\u79cd\u4ee3\u6570\uff0c\u4ee5\u7814\u7a76\u903b\u8f91\u63a8\u7406\u7684\u57fa\u672c\u539f\u5219\u3002
\u5e94\u7528\uff1a\u8868\u793a\u6709\u9650\u96c6\u5408\u3002\u6bd4\u5982A={0,3,5,6} \u53ef\u4ee5\u8868\u793a\u4e3aa=[01101001]\uff1bB={0,2,4,6} \u8868\u793a\u4e3a b=[01010101]\u3002\u7136\u540e\u53ef\u4ee5\u7528\u8fc7\u4f4d\u8fd0\u7b97\u6765\u83b7\u5f97A\u222aB\uff08a^b\uff09\uff0cA\u2229B\uff08a&b\uff09\u3002<\/p>\n\n\n\n

2.1.8 C\u8bed\u8a00\u4e2d\u7684\u4f4d\u7ea7\u8fd0\u7b97<\/h3>\n\n\n\n

C\u8bed\u8a00\u6240\u4f7f\u7528\u7684\uff1a|\uff08OR\uff09\uff0c&\uff08AND\uff09\uff0c~\uff08NOT\uff09\uff0c^\uff08EXCLUSIVE-OR\uff09\u3002<\/p>\n\n\n\n

2.1.9 C\u8bed\u8a00\u4e2d\u7684\u903b\u8f91\u8fd0\u7b97<\/h3>\n\n\n\n

C\u8bed\u8a00\u6240\u4f7f\u7528\u7684\uff1a||\u3001&&\u548c\uff01\u3002\u5206\u522b\u5bf9\u5e94\u547d\u9898\u903b\u8f91\u4e2d\u7684OR\u3001AND\u548cNOT\u3002<\/p>\n\n\n\n

2.1.10 C\u8bed\u8a00\u4e2d\u7684\u4f4d\u79fb\u8fd0\u7b97<\/h3>\n\n\n\n

C\u8bed\u8a00\u6240\u4f7f\u7528\u7684\uff1a<<\uff08\u5de6\u79fb\uff09\u3001>>\uff08\u7b97\u672f\u53f3\u79fb\uff1a\u9ad8\u4f4d\u8865\u7b26\u53f7\u4f4d\uff09\u3001>>>\uff08\u903b\u8f91\u53f3\u79fb\uff1a\u9ad8\u4f4d\u88650\uff09\u3002
\u5b9e\u9645\u4e0a\uff0c\u51e0\u4e4e\u6240\u6709\u7684\u7f16\u8bd1\u5668\/\u53ca\u5176\u7ec4\u5408\u90fd\u5bf9\u6709\u7b26\u53f7\u6570\u636e\u4f7f\u7528\u7b97\u672f\u53f3\u79fb\uff0c\u4e14\u8bb8\u591a\u7a0b\u5e8f\u5458\u4e5f\u4f1a\u5047\u8bbe\u673a\u5668\u4f1a\u4f7f\u7528\u8fd9\u79cd\u53f3\u79fb\u3002<\/p>\n\n\n\n

\u79fb\u52a8k\u4f4d\uff0c\u8fd9\u91cck\u5f88\u5927<\/h4>\n\n\n\n

\u5bf9\u4e8e\u4e00\u4e2aw\u4f4d\u7ec4\u6210\u7684\u6570\u636e\u7c7b\u578b\uff0c\u5982\u679c\u79fb\u52a8k\u4f4d\uff0ck>=w\u65f6\uff0c\u79fb\u4f4d\u6307\u4ee4\u53ea\u4f1a\u8003\u8651log2<\/sub>w\u4f4d\uff0c\u56e0\u6b64\u5c31\u76f8\u5f53\u4e8e\u79fb\u52a8\u4e86k mod w\u4f4d\u3002<\/p>\n\n\n\n

\u4f18\u5148\u7ea7\uff1aC\u8bed\u8a00\u4e2d\u79fb\u4f4d\u64cd\u4f5c\u7b26\u7684\u4f18\u5148\u7ea7\u4f4e\u4e8e\u52a0\u51cf\u6cd5\uff0c\u56e0\u6b64\u8fd0\u7b97\u4e2d\u9700\u8981\u6dfb\u52a0\u62ec\u53f7\u3002<\/p>\n\n\n\n

2.2 \u6574\u6570\u8868\u793a<\/h2>\n\n\n\n

2.2.1 \u6574\u578b\u6570\u636e\u7c7b\u578b<\/h3>\n\n\n\n

\u4e0d\u540c\u673a\u5668\u7684\u6574\u578b\u6570\u636e\u53d6\u503c\u8303\u56f4\u4f1a\u6709\u6240\u4e0d\u540c\uff1a<\/p>\n\n\n\n

C\u6570\u636e\u7c7b\u578b<\/td>\u6700\u5c0f\u503c<\/td>\u6700\u5927\u503c<\/td><\/tr>
char<\/td>-128<\/td>127<\/td><\/tr>
unsigned char<\/td>0<\/td>255<\/td><\/tr>
short [int]<\/td>-32 768<\/td>32 767<\/td><\/tr>
unsigned short [int]<\/td>0<\/td>65 535<\/td><\/tr>
int<\/td>-2 147 483 648<\/td>2 147 483 647<\/td><\/tr>
unsigned [int]<\/td>0<\/td>4 294 967 295<\/td><\/tr>
long [int]<\/td>-2 147 483 648<\/td>2 147 483 647<\/td><\/tr>
unsigned long [int]<\/td>0<\/td>4 294 967 295<\/td><\/tr>
long long [int]<\/td>-9 223 372 036 854 775 808<\/td>9 223 372 036 854 775 807<\/td><\/tr>
unsigned long long [int]<\/td>0<\/td>18 446 744 073 709 551 615<\/td><\/tr><\/tbody><\/table>
32\u4f4d\u673a\u5668\u4e0aC\u8bed\u8a00\u6574\u6570\u5178\u578b\u53d6\u503c\u8303\u56f4<\/figcaption><\/figure>\n\n\n\n
C\u6570\u636e\u7c7b\u578b<\/td>\u6700\u5c0f\u503c<\/td>\u6700\u5927\u503c<\/td><\/tr>
char<\/td>-128<\/td>127<\/td><\/tr>
unsigned char<\/td>0<\/td>255<\/td><\/tr>
short [int]<\/td>-32 768<\/td>32 767<\/td><\/tr>
unsigned short [int]<\/td>0<\/td>65 535<\/td><\/tr>
int<\/td>-2 147 483 648<\/td>2 147 483 647<\/td><\/tr>
unsigned [int]<\/td>0<\/td>4 294 967 295<\/td><\/tr>
long [int]<\/td>-9 223 372 036 854 775 808<\/mark><\/td>9 223 372 036 854 775 807<\/mark><\/td><\/tr>
unsigned long [int]<\/td>0<\/mark><\/td>18 446 744 073 709 551 615<\/mark><\/td><\/tr>
long long [int]<\/td>-9 223 372 036 854 775 808<\/td>9 223 372 036 854 775 807<\/td><\/tr>
unsigned long long [int]<\/td>0<\/td>18 446 744 073 709 551 615<\/td><\/tr><\/tbody><\/table>
64\u4f4d\u673a\u5668\u4e0aC\u8bed\u8a00\u6574\u6570\u5178\u578b\u53d6\u503c\u8303\u56f4<\/figcaption><\/figure>\n\n\n\n
C\u6570\u636e\u7c7b\u578b<\/td>\u6700\u5c0f\u503c<\/td>\u6700\u5927\u503c<\/td><\/tr>
char<\/td>-127<\/mark><\/td>127<\/td><\/tr>
unsigned char<\/td>0<\/td>255<\/td><\/tr>
short [int]<\/td>-32 767<\/mark><\/td>32 767<\/td><\/tr>
unsigned short [int]<\/td>0<\/td>65 535<\/td><\/tr>
int<\/td>-32 767<\/mark><\/td>32 767<\/mark><\/td><\/tr>
unsigned [int]<\/td>0<\/td>65 535<\/mark><\/td><\/tr>
long [int]<\/td>-2 147 483 647<\/mark><\/td>2 147 483 647<\/mark><\/td><\/tr>
unsigned long [int]<\/td>0<\/mark><\/td>4 294 967 295<\/mark><\/td><\/tr>
long long [int]<\/td>-9 223 372 036 854 775 807<\/mark><\/td>9 223 372 036 854 775 807<\/td><\/tr>
unsigned long long [int]<\/td>0<\/td>18 446 744 073 709 551 615<\/td><\/tr><\/tbody><\/table>
C\u8bed\u8a00\u6574\u6570\u4fdd\u8bc1\u7684\u53d6\u503c\u8303\u56f4
\u6ce8\uff1aC\u8bed\u8a00\u6807\u51c6\u8981\u6c42\u8fd9\u4e9b\u6570\u636e\u7c7b\u578b\u81f3\u5c11\u6709\u8fd9\u6837\u7684\u53d6\u503c\u8303\u56f4\u3002<\/figcaption><\/figure>\n\n\n\n

2.2.2 \u65e0\u7b26\u53f7\u6570\u7684\u7f16\u7801<\/h3>\n\n\n\n

\u5047\u8bbe\u4e00\u4e2a\u6570\u6709$w$\u4f4d\uff0c\u7528$\\vec x$\u8868\u793ax\u7684\u5411\u91cf\uff0c\u6216\u8005\u5199\u6210$[x_{w-1},x_{w-2},\\cdots,x_0]$\u3002<\/p>\n\n\n\n

$$B2U_w(\\vec x)=\\displaystyle\\sum_{i=0}^{w-1}x_i2^i$$<\/p>\n\n\n\n

B2U\u53d6\u503c\u8303\u56f4$(0 \\leq B2U \\leq 2^w-1)$<\/p>\n\n\n\n

2.2.3 \u8865\u7801\u7f16\u7801<\/h3>\n\n\n\n

\u5982\u679c\u8981\u8868\u793a\u8d1f\u503c\uff0c\u6700\u5e38\u7528\u7684\u8868\u793a\u65b9\u5f0f\u5c31\u662f\u8865\u7801\uff08two`s-complement\uff09\u3002<\/p>\n\n\n\n

$$B2T_w(\\vec x)=-x_{w-1}2^{w-1}+\\displaystyle\\sum^{w-2}_{i=0}x_i2^i$$<\/p>\n\n\n\n

B2T\u53d6\u503c\u8303\u56f4$(-2^{w-1} \\leq B2T \\leq 2^{w-1}-1)$<\/p>\n\n\n\n

2.2.4 \u6709\u7b26\u53f7\u6570\u548c\u65e0\u7b26\u53f7\u6570\u4e4b\u95f4\u7684\u8f6c\u6362<\/h3>\n\n\n\n

\u5bf9\u5927\u591a\u6570C\u8bed\u8a00\u7684\u89c4\u5219\u662f\uff1a\u6570\u503c\u53ef\u80fd\u4f1a\u6539\u53d8\uff0c\u4f46\u662f\u4f4d\u6a21\u5f0f\u4e0d\u53d8\u3002<\/p>\n\n\n\n

$$U2T_w(u)=B2T_w(U2B_w(u))=-u_{w-1}2^w+u$$<\/p>\n\n\n\n

$$U2T_w(u)=\\begin{cases}u,&u<2^w-1\\\\[2ex]u-2^w,&u\\geq2^w-1\\\\[2ex]\\end{cases}$$<\/p>\n\n\n\n

$$T2U_w(x)=B2U_w(T2B_w(x))=x_{w-1}2^w+x$$<\/p>\n\n\n\n

$$T2U_w(x)=\\begin{cases}x+2^w,&x<0\\\\[2ex]x,&x\\geq0\\\\[2ex]\\end{cases}$$<\/p>\n\n\n\n

\u6709\u7b26\u53f7\u548c\u65e0\u7b26\u53f7\u6570\u4e4b\u95f4\u7684\u8f6c\u6362\uff1a$0$~$2^{w-1}-1$\u4e0d\u53d8\uff0c$2^{w-1}$~$2^w-1$\u6620\u5c04\u5230$-2^w-1$~$-1$\u3002<\/p>\n\n\n\n

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\"\"<\/figure>\n<\/div>\n\n\n\n
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\"\"<\/figure>\n<\/div>\n<\/div>\n\n\n\n

2.2.5 C\u8bed\u8a00\u4e2d\u7684\u6709\u7b26\u53f7\u6570\u4e0e\u65e0\u7b26\u53f7\u6570<\/h3>\n\n\n\n

\u5982\u679c\u4e00\u4e2a\u8868\u8fbe\u5f0f\u540c\u65f6\u5305\u542b\u6709\u7b26\u53f7\u6570\u548c\u65e0\u7b26\u53f7\u6570\uff0c\u90a3\u4e48C\u8bed\u8a00\u4f1a\u9690\u5f0f\u7684\u5c06\u6709\u7b26\u53f7\u6570\u5f3a\u5236\u8f6c\u6362\u6210\u65e0\u7b26\u53f7\u6570\uff0c\u5e76\u5047\u8bbe\u8fd9\u4e24\u4e2a\u6570\u90fd\u662f\u975e\u8d1f\u7684\u3002\u8fd9\u6837\u4f1a\u51fa\u73b0\u4e00\u4e9b\u5947\u7279\u7684\u73b0\u8c61\uff1a<\/p>\n\n\n\n

\u8868\u8fbe\u5f0f<\/td>\u7c7b\u578b<\/td>\u6c42\u503c<\/td><\/tr>
0 == 0U<\/td>\u65e0\u7b26\u53f7<\/td>1<\/td><\/tr>
-1 < 0<\/td>\u6709\u7b26\u53f7<\/td>1<\/td><\/tr>
-1 < 0U<\/td>\u65e0\u7b26\u53f7<\/td>0*<\/td><\/tr>
2147483647 > -2147483647-11<\/a><\/sup><\/td>\u6709\u7b26\u53f7<\/td>1<\/td><\/tr>
2147483647U > -2147483647-1<\/td>\u65e0\u7b26\u53f7<\/td>0*<\/td><\/tr>
2147483647 > (int)-2147483648U<\/td>\u6709\u7b26\u53f7<\/td>1*<\/td><\/tr>
-1 > -2<\/td>\u6709\u7b26\u53f7<\/td>1<\/td><\/tr>
(unsigned) -1 > -2<\/td>\u65e0\u7b26\u53f7<\/td>1<\/td><\/tr><\/tbody><\/table>
\u6ce8\uff1a\u975e\u76f4\u89c2\u7684\u60c5\u51b5\u6807\u6ce8\u4e86’*’\u3002<\/figcaption><\/figure>\n\n\n\n

2.2.6 \u6269\u5c55\u4e00\u4e2a\u6570\u5b57\u7684\u4f4d\u8868\u793a<\/h3>\n\n\n\n