{"id":82,"date":"2026-09-14T15:57:44","date_gmt":"2026-09-14T07:57:44","guid":{"rendered":"https:\/\/decagrammaton.xyz\/?p=82"},"modified":"2026-09-17T16:00:54","modified_gmt":"2026-09-17T08:00:54","slug":"08-c%e8%af%ad%e8%a8%80%e6%8c%87%e9%92%88","status":"publish","type":"post","link":"https:\/\/decagrammaton.xyz\/?p=82","title":{"rendered":"08-C\u8bed\u8a00\u6307\u9488"},"content":{"rendered":"\n
\n\n\n\n

\u901a\u8fc7\u6307\u9488\uff0c\u53ef\u4ee5\u7b80\u5316\u4e00\u4e9b C\n\u7f16\u7a0b\u4efb\u52a1\u7684\u6267\u884c\uff0c\u8fd8\u6709\u4e00\u4e9b\u4efb\u52a1\uff0c\u5982\u52a8\u6001\u5185\u5b58\u5206\u914d\uff0c\u6ca1\u6709\u6307\u9488\u662f\u65e0\u6cd5\u6267\u884c\u7684\u3002\u6240\u4ee5\uff0c\u60f3\u8981\u6210\u4e3a\u4e00\u540d\u4f18\u79c0\u7684\nC \u7a0b\u5e8f\u5458\uff0c\u5b66\u4e60\u6307\u9488\u662f\u5f88\u6709\u5fc5\u8981\u7684\u3002<\/p>\n\n\n\n

\n\n\n\n

1. \u4ec0\u4e48\u662f\u6307\u9488<\/h1>\n\n\n\n

\u6307\u9488\u5c31\u662f\u4e00\u4e2a\u7528\u6765\u4fdd\u5b58\u5730\u5740\u7684\u53d8\u91cf\uff0c*p\n\u53ef\u4ee5\u901a\u8fc7\u8fd9\u4e2a\u5730\u5740\u8bbf\u95ee\u5bf9\u5e94\u7684\u6570\u636e\u3002<\/p>\n\n\n\n

\u4f7f\u7528\u4f8b:<\/p>\n\n\n\n

<\/a>int<\/span>    *<\/span>ip;<\/span>    \/* \u4e00\u4e2a\u6574\u578b\u7684\u6307\u9488 *\/<\/span><\/span>\n<\/a>double<\/span> *<\/span>dp;<\/span>    \/* \u4e00\u4e2a double \u578b\u7684\u6307\u9488 *\/<\/span><\/span>\n<\/a>float<\/span>  *<\/span>fp;<\/span>    \/* \u4e00\u4e2a\u6d6e\u70b9\u578b\u7684\u6307\u9488 *\/<\/span><\/span>\n<\/a>char<\/span>   *<\/span>ch;<\/span>    \/* \u4e00\u4e2a\u5b57\u7b26\u578b\u7684\u6307\u9488 *\/<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5185\u5b58\u5730\u5740<\/h2>\n\n\n\n
\u7a0b\u5e8f\u8fd0\u884c\u65f6\uff0c\u53d8\u91cf\u4f1a\u88ab\u5b58\u653e\u5728\u8ba1\u7b97\u673a\u7684\u5185\u5b58\u4e2d\u3002<\/p>\n\n\n\n
\u6bcf\u4e00\u5757\u5185\u5b58\u90fd\u6709\u4e00\u4e2a\u81ea\u5df1\u7684\u7f16\u53f7\uff0c\u8fd9\u4e2a\u7f16\u53f7\u5c31\u662f\u5185\u5b58\u5730\u5740<\/strong>\u3002<\/p>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>#include <\/span><stdio.h><\/span><\/span>\n<\/a><\/span>\n<\/a>int<\/span> main()<\/span> {<\/span><\/span>\n<\/a><\/span>\n<\/a>    int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a><\/span>\n<\/a>    printf(<\/span>\"a\u7684\u503c\uff1a<\/span>%d\\n<\/span>\"<\/span>,<\/span> a);<\/span><\/span>\n<\/a>    printf(<\/span>\"a\u7684\u5730\u5740\uff1a<\/span>%p\\n<\/span>\"<\/span>,<\/span> &<\/span>a);<\/span><\/span>\n<\/a><\/span>\n<\/a>    return<\/span> 0<\/span>;<\/span><\/span>\n<\/a>}<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd0\u884c\u7ed3\u679c\u53ef\u80fd\u662f\uff1a<\/p>\n\n\n\n
a\u7684\u503c\uff1a10\na\u7684\u5730\u5740\uff1a000000000061FE1C \/\/\u5730\u5740\u4e0d\u662f\u6bcf\u6b21\u8fd0\u884c\u90fd\u4e00\u6837\uff0c\u4f7f\u7528\u4e0d\u662f\u786c\u7f16\u5199<\/code><\/pre>\n\n\n\n
\u8fd9\u91cc\uff1a<\/p>\n\n\n\n
<\/a>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\u53d8\u91cf a<\/code> \u4e2d\u4fdd\u5b58\u7684\u6570\u636e\uff1a<\/p>\n\n\n\n
10<\/code><\/pre>\n\n\n\n
\u800c\uff1a<\/p>\n\n\n\n
<\/a>&<\/span>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\u83b7\u53d6\u53d8\u91cf a<\/code> \u7684\u5185\u5b58\u5730\u5740\u3002<\/p>\n\n\n\n
\u6240\u4ee5\u53ef\u4ee5\u7b80\u5355\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n
\u53d8\u91cf a\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502      10      \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n       \u2191\n       \u2502\n      &a\n       \u2502\n       \u25bc\n   \u5185\u5b58\u5730\u5740<\/code><\/pre>\n\n\n\n
\u4f7f\u7528 %p<\/code> \u67e5\u770b\u5730\u5740<\/h3>\n\n\n\n
\u4f7f\u7528 printf()<\/code> \u8f93\u51fa\u5185\u5b58\u5730\u5740\u65f6\uff0c\u9700\u8981\u4f7f\u7528\uff1a<\/p>\n\n\n\n
<\/a>%<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%p\\n<\/span>\"<\/span>,<\/span> &<\/span>a);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u901a\u5e38\u8fd8\u4f1a\u5c06\u5730\u5740\u8f6c\u6362\u6210 void *<\/code>\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%p\\n<\/span>\"<\/span>,<\/span> (<\/span>void<\/span> *)&<\/span>a);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u91cc\u7684\uff1a<\/p>\n\n\n\n
<\/a>&<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53eb\u505a\u53d6\u5730\u5740\u8fd0\u7b97\u7b26<\/strong>\u3002<\/p>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a><\/span>\n<\/a>&<\/span>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u5c31\u662f\uff1a<\/p>\n\n\n\n
\n
\u83b7\u53d6\u53d8\u91cf a<\/code> \u7684\u5185\u5b58\u5730\u5740\u3002<\/p>\n<\/blockquote>\n\n\n\n
\n\n\n\n
\u5730\u5740\u548c\u6570\u636e<\/h2>\n\n\n\n
\u8981\u533a\u5206\u4e24\u4e2a\u6982\u5ff5\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5176\u4e2d\uff1a<\/p>\n\n\n\n
a   \u2192 \u53d8\u91cf\n10  \u2192 \u53d8\u91cf\u4fdd\u5b58\u7684\u6570\u636e\n&a  \u2192 \u53d8\u91cf\u7684\u5730\u5740<\/code><\/pre>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u6210\uff1a<\/p>\n\n\n\n
          \u5730\u5740\n           \u2502\n           \u25bc\n      \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n      \u2502   10    \u2502\n      \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n           \u25b2\n           \u2502\n           a<\/code><\/pre>\n\n\n\n
\u56e0\u6b64\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> a);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u662f\u5728\u67e5\u770b a<\/code> \u4fdd\u5b58\u7684\u6570\u636e\u3002<\/p>\n\n\n\n
\u800c\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%p\\n<\/span>\"<\/span>,<\/span> &<\/span>a);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u662f\u5728\u67e5\u770b a<\/code> \u6240\u5728\u7684\u5185\u5b58\u5730\u5740\u3002<\/p>\n\n\n\n
\u8bb0\u4f4f\uff1a<\/strong><\/p>\n\n\n\n
a   \u2192 \u503c\n&a  \u2192 \u5730\u5740<\/code><\/pre>\n\n\n\n
\u8fd9\u4e5f\u662f\u5b66\u4e60\u6307\u9488\u6700\u91cd\u8981\u7684\u57fa\u7840\u3002<\/p>\n\n\n\n
\u901a\u8fc7\u6307\u9488\u4fdd\u5b58\u5730\u5740<\/h2>\n\n\n\n
\u524d\u9762\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\uff1a<\/p>\n\n\n\n
<\/a>&<\/span>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u83b7\u53d6\u53d8\u91cf a<\/code> \u7684\u5730\u5740\u3002<\/p>\n\n\n\n
\u5982\u679c\u60f3\u628a\u8fd9\u4e2a\u5730\u5740\u4fdd\u5b58\u4e0b\u6765\uff0c\u5c31\u53ef\u4ee5\u4f7f\u7528\u6307\u9488\u53d8\u91cf\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u91cc\u53ef\u4ee5\u62c6\u5f00\u7406\u89e3\uff1a<\/p>\n\n\n\n
int *p<\/code><\/pre>\n\n\n\n
\u8868\u793a\u521b\u5efa\u4e00\u4e2a int<\/code> \u7c7b\u578b\u7684\u6307\u9488\u53d8\u91cf p<\/code>\u3002<\/p>\n\n\n\n
&a<\/code><\/pre>\n\n\n\n
\u8868\u793a\u83b7\u53d6\u53d8\u91cf a<\/code> \u7684\u5730\u5740\u3002<\/p>\n\n\n\n
\u6240\u4ee5\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5c31\u662f\uff1a<\/p>\n\n\n\n
\n
\u521b\u5efa\u4e00\u4e2a\u6307\u5411 int<\/code> \u7c7b\u578b\u6570\u636e\u7684\u6307\u9488\np<\/code>\uff0c\u5e76\u8ba9\u5b83\u4fdd\u5b58\u53d8\u91cf a<\/code> \u7684\u5730\u5740\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>#include <\/span><stdio.h><\/span><\/span>\n<\/a><\/span>\n<\/a>int<\/span> main()<\/span> {<\/span><\/span>\n<\/a><\/span>\n<\/a>    int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a><\/span>\n<\/a>    int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span>\n<\/a><\/span>\n<\/a>    printf(<\/span>\"a\u7684\u503c\uff1a<\/span>%d\\n<\/span>\"<\/span>,<\/span> a);<\/span><\/span>\n<\/a>    printf(<\/span>\"a\u7684\u5730\u5740\uff1a<\/span>%p\\n<\/span>\"<\/span>,<\/span> (<\/span>void<\/span> *)&<\/span>a);<\/span><\/span>\n<\/a>    printf(<\/span>\"p\u4fdd\u5b58\u7684\u5730\u5740\uff1a<\/span>%p\\n<\/span>\"<\/span>,<\/span> (<\/span>void<\/span> *)<\/span>p);<\/span><\/span>\n<\/a><\/span>\n<\/a>    return<\/span> 0<\/span>;<\/span><\/span>\n<\/a>}<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u770b\u5230\uff1a<\/p>\n\n\n\n
a\u7684\u503c\uff1a10\na\u7684\u5730\u5740\uff1a000000000061FE1C\np\u4fdd\u5b58\u7684\u5730\u5740\uff1a000000000061FE1C<\/code><\/pre>\n\n\n\n
\u4e5f\u5c31\u662f\u8bf4\uff1a<\/p>\n\n\n\n
        a\n        \u2502\n        \u25bc\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502       10        \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n        \u25b2\n        \u2502\n        \u2502 \u5730\u5740\n        \u2502\n        p<\/code><\/pre>\n\n\n\n
\u6b64\u65f6\uff1a<\/p>\n\n\n\n
<\/a>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a a<\/code> \u7684\u503c\u3002<\/p>\n\n\n\n
<\/a>&<\/span>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a a<\/code> \u7684\u5730\u5740\u3002<\/p>\n\n\n\n
<\/a>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a p<\/code> \u4e2d\u4fdd\u5b58\u7684\u5730\u5740\u3002<\/p>\n\n\n\n
<\/a>*<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u5219\u53ef\u4ee5\u901a\u8fc7\u8fd9\u4e2a\u5730\u5740\u8bbf\u95ee a<\/code> \u4e2d\u7684\u6570\u636e\u3002<\/p>\n\n\n\n
\u56e0\u6b64\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8f93\u51fa\uff1a<\/p>\n\n\n\n
10<\/code><\/pre>\n\n\n\n
\u53ef\u4ee5\u8bb0\u6210\uff1a<\/p>\n\n\n\n
a      \u2192 10\n&a     \u2192 a\u7684\u5730\u5740\np      \u2192 a\u7684\u5730\u5740\n*p     \u2192 10<\/code><\/pre>\n\n\n\n
\u6838\u5fc3\u5173\u7cfb\uff1a<\/strong><\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5c31\u662f\uff1a<\/p>\n\n\n\n
       &a\n        \u2193\n      \u5730\u5740\n        \u2193\n        p\n        \u2193\n       *p\n        \u2193\n       a\n        \u2193\n       10<\/code><\/pre>\n\n\n\n
\u6307\u9488\u53d8\u91cf<\/h2>\n\n\n\n
\u524d\u9762\u6211\u4eec\u77e5\u9053\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u901a\u8fc7\uff1a<\/p>\n\n\n\n
<\/a>&<\/span>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u83b7\u53d6\u53d8\u91cf a<\/code> \u7684\u5730\u5740\u3002<\/p>\n\n\n\n
\u5982\u679c\u60f3\u4fdd\u5b58\u8fd9\u4e2a\u5730\u5740\uff0c\u5c31\u9700\u8981\u4f7f\u7528\u6307\u9488\u53d8\u91cf<\/strong>\u3002<\/p>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5176\u4e2d\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\u521b\u5efa\u4e00\u4e2a int<\/code> \u7c7b\u578b\u7684\u6307\u9488\u53d8\u91cf p<\/code>\u3002<\/p>\n\n\n\n
\u800c\uff1a<\/p>\n\n\n\n
<\/a>&<\/span>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\u83b7\u53d6\u53d8\u91cf a<\/code> \u7684\u5730\u5740\u3002<\/p>\n\n\n\n
\u6240\u4ee5\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\uff1a<\/p>\n\n\n\n
\n
\u521b\u5efa\u4e00\u4e2a int<\/code> \u7c7b\u578b\u7684\u6307\u9488\u53d8\u91cf p<\/code>\uff0c\u5e76\u5c06\na<\/code> \u7684\u5730\u5740\u4fdd\u5b58\u5230 p<\/code> \u4e2d\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n
\u53d8\u91cf a\n\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502      10      \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n       \u25b2\n       \u2502\n       \u2502 \u5730\u5740\n       \u2502\n       p<\/code><\/pre>\n\n\n\n
\u6b64\u65f6\uff1a<\/p>\n\n\n\n
<\/a>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a a<\/code> \u4e2d\u4fdd\u5b58\u7684\u6570\u636e\u3002<\/p>\n\n\n\n
<\/a>&<\/span>a<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a a<\/code> \u7684\u5730\u5740\u3002<\/p>\n\n\n\n
<\/a>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a p<\/code> \u4e2d\u4fdd\u5b58\u7684\u5730\u5740\u3002<\/p>\n\n\n\n
<\/a>*<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\u901a\u8fc7 p<\/code> \u4fdd\u5b58\u7684\u5730\u5740\u8bbf\u95ee\u5bf9\u5e94\u7684\u6570\u636e\u3002<\/p>\n\n\n\n
\u56e0\u6b64\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span>\n<\/a><\/span>\n<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> a);<\/span><\/span>\n<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8f93\u51fa\uff1a<\/p>\n\n\n\n
10\n10<\/code><\/pre>\n\n\n\n
\u867d\u7136\u8bbf\u95ee\u65b9\u5f0f\u4e0d\u540c\uff0c\u4f46\u8bbf\u95ee\u7684\u662f\u540c\u4e00\u4e2a\u6570\u636e<\/strong>\u3002<\/p>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n
\u76f4\u63a5\u8bbf\u95ee\uff1a\n\na\n\u2193\n10\n\n\n\u901a\u8fc7\u6307\u9488\u8bbf\u95ee\uff1a\n\np\n\u2193\na \u7684\u5730\u5740\n\u2193\n*p\n\u2193\n10<\/code><\/pre>\n\n\n\n
*<\/code> \u7684\u4e24\u79cd\u542b\u4e49<\/h3>\n\n\n\n
\u9700\u8981\u6ce8\u610f\uff0c*<\/code> \u5728\u4e0d\u540c\u4f4d\u7f6e\u6709\u4e0d\u540c\u542b\u4e49\u3002<\/p>\n\n\n\n
\u58f0\u660e\u6307\u9488\u65f6\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a p<\/code> \u662f\u4e00\u4e2a\u6307\u9488\u53d8\u91cf\u3002<\/p>\n\n\n\n
\u4f7f\u7528\u6307\u9488\u65f6\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\u5bf9 p<\/code> \u8fdb\u884c\u89e3\u5f15\u7528<\/strong>\uff0c\u901a\u8fc7\np<\/code> \u4e2d\u4fdd\u5b58\u7684\u5730\u5740\u8bbf\u95ee\u6570\u636e\u3002<\/p>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span>\n<\/a><\/span>\n<\/a>*<\/span>p =<\/span> 20<\/span>;<\/span><\/span>\n<\/a><\/span>\n<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> a);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8f93\u51fa\uff1a<\/p>\n\n\n\n
20<\/code><\/pre>\n\n\n\n
\u56e0\u4e3a p<\/code> \u4fdd\u5b58\u7684\u662f a<\/code> \u7684\u5730\u5740\uff0c\u6240\u4ee5\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>p =<\/span> 20<\/span>;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5b9e\u9645\u4e0a\u4fee\u6539\u7684\u662f a<\/code> \u6240\u5728\u5185\u5b58\u4e2d\u7684\u6570\u636e\u3002<\/p>\n\n\n\n
\u56e0\u6b64\uff1a<\/p>\n\n\n\n
a      \u2192 10\n&a     \u2192 a\u7684\u5730\u5740\np      \u2192 a\u7684\u5730\u5740\n*p     \u2192 10<\/code><\/pre>\n\n\n\n
\u4fee\u6539\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>p =<\/span> 20<\/span>;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u4e4b\u540e\uff1a<\/p>\n\n\n\n
a      \u2192 20\n*p     \u2192 20<\/code><\/pre>\n\n\n\n
\u8fd9\u5c31\u662f\u6307\u9488\u6700\u57fa\u672c\u7684\u4f5c\u7528\uff1a<\/p>\n\n\n\n
\n
\u901a\u8fc7\u5730\u5740\u95f4\u63a5\u8bbf\u95ee\u548c\u4fee\u6539\u6570\u636e\u3002<\/strong><\/p>\n<\/blockquote>\n\n\n\n
\u6307\u9488\u7684\u7c7b\u578b<\/h2>\n\n\n\n
\u6307\u9488\u4e5f\u6709\u81ea\u5df1\u7684\u7c7b\u578b\u3002<\/p>\n\n\n\n
\u5e38\u89c1\u7684\u6307\u9488\u7c7b\u578b\u6709\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p;<\/span>       \/\/ int \u7c7b\u578b\u6307\u9488<\/span><\/span>\n<\/a>char<\/span> *<\/span>p;<\/span>      \/\/ char \u7c7b\u578b\u6307\u9488<\/span><\/span>\n<\/a>float<\/span> *<\/span>p;<\/span>     \/\/ float \u7c7b\u578b\u6307\u9488<\/span><\/span>\n<\/a>double<\/span> *<\/span>p;<\/span>    \/\/ double \u7c7b\u578b\u6307\u9488<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u91cc\uff1a<\/p>\n\n\n\n
a    \u2192 int \u7c7b\u578b\np    \u2192 int* \u7c7b\u578b<\/code><\/pre>\n\n\n\n
\u8868\u793a p<\/code> \u662f\u4e00\u4e2a\u6307\u5411 int<\/code> \u7c7b\u578b\u6570\u636e\u7684\u6307\u9488\u3002<\/p>\n\n\n\n
\n\n\n\n
\u4e3a\u4ec0\u4e48\u6307\u9488\u9700\u8981\u7c7b\u578b\uff1f<\/h3>\n\n\n\n
\u6307\u9488\u4fdd\u5b58\u7684\u4e3b\u8981\u662f\u4e00\u4e2a\u5185\u5b58\u5730\u5740<\/strong>\u3002<\/p>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n
p\n\u2502\n\u2502 \u4fdd\u5b58\u5730\u5740\n\u25bc\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502     10      \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n     int<\/code><\/pre>\n\n\n\n
\u4f46\u662f\uff0c\u4ec5\u4ec5\u77e5\u9053\u4e00\u4e2a\u5730\u5740\u8fd8\u4e0d\u591f\u3002<\/p>\n\n\n\n
C \u8bed\u8a00\u8fd8\u9700\u8981\u77e5\u9053\uff1a<\/p>\n\n\n\n
\n
\u8fd9\u4e2a\u5730\u5740\u4e2d\u7684\u6570\u636e\u5e94\u8be5\u6309\u7167\u4ec0\u4e48\u7c7b\u578b\u6765\u8bfb\u53d6\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\uff1a<\/p>\n\n\n\n
\n
p<\/code> \u6307\u5411\u7684\u6570\u636e\u6309\u7167 int<\/code> \u7c7b\u578b\u5904\u7406\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u800c\uff1a<\/p>\n\n\n\n
<\/a>char<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\uff1a<\/p>\n\n\n\n
\n
p<\/code> \u6307\u5411\u7684\u6570\u636e\u6309\u7167 char<\/code> \u7c7b\u578b\u5904\u7406\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u6240\u4ee5\uff1a<\/p>\n\n\n\n
int *     \u2192 \u6307\u5411 int \u6570\u636e\nchar *    \u2192 \u6307\u5411 char \u6570\u636e\nfloat *   \u2192 \u6307\u5411 float \u6570\u636e\ndouble *  \u2192 \u6307\u5411 double \u6570\u636e<\/code><\/pre>\n\n\n\n
\n\n\n\n
\u6307\u9488\u7c7b\u578b\u548c\u89e3\u5f15\u7528<\/h2>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u56e0\u4e3a p<\/code> \u662f int *<\/code> \u7c7b\u578b\uff0c\u6240\u4ee5\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u4f1a\u6309\u7167 int<\/code> \u7c7b\u578b\u8bbf\u95ee a<\/code>\u3002<\/p>\n\n\n\n
\u56e0\u6b64\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u6b63\u786e\u8f93\u51fa\uff1a<\/p>\n\n\n\n
10<\/code><\/pre>\n\n\n\n
\u518d\u770b\uff1a<\/p>\n\n\n\n
<\/a>char<\/span> c =<\/span> 'A'<\/span>;<\/span><\/span>\n<\/a>char<\/span> *<\/span>p =<\/span> &<\/span>c;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u91cc p<\/code> \u662f char *<\/code> \u7c7b\u578b\u3002<\/p>\n\n\n\n
\u6240\u4ee5\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u4f1a\u6309\u7167 char<\/code> \u7c7b\u578b\u8bbf\u95ee c<\/code>\u3002<\/p>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%c\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8f93\u51fa\uff1a<\/p>\n\n\n\n
A<\/code><\/pre>\n\n\n\n
\n\n\n\n
\u6307\u9488\u7c7b\u578b\u51b3\u5b9a\u6307\u9488\u79fb\u52a8\u7684\u5927\u5c0f<\/h2>\n\n\n\n
\u6307\u9488\u7c7b\u578b\u8fd8\u6709\u4e00\u4e2a\u975e\u5e38\u91cd\u8981\u7684\u4f5c\u7528\uff1a<\/p>\n\n\n\n
\u6307\u9488\u8fdb\u884c\u52a0\u51cf\u8fd0\u7b97\u65f6\uff0c\u4f1a\u6839\u636e\u6307\u9488\u6307\u5411\u7684\u6570\u636e\u7c7b\u578b\u79fb\u52a8\u76f8\u5e94\u7684\u5927\u5c0f\u3002<\/strong><\/p>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a[<\/span>3<\/span>]<\/span> =<\/span> {<\/span>10<\/span>,<\/span> 20<\/span>,<\/span> 30<\/span>};<\/span><\/span>\n<\/a><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> a;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5047\u8bbe\uff1a<\/p>\n\n\n\n
sizeof(int) = 4<\/code><\/pre>\n\n\n\n
\u90a3\u4e48\u6570\u7ec4\u53ef\u80fd\u662f\uff1a<\/p>\n\n\n\n
\u5730\u5740\n1000        1004        1008\n \u2193           \u2193           \u2193\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2510   \u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502  10  \u2502   \u2502  20  \u2502   \u2502  30  \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2518   \u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n   a[0]       a[1]       a[2]<\/code><\/pre>\n\n\n\n
\u6b64\u65f6\uff1a<\/p>\n\n\n\n
<\/a>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u6307\u5411 a[0]<\/code>\u3002<\/p>\n\n\n\n
\u6267\u884c\uff1a<\/p>\n\n\n\n
<\/a>p++;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5e76\u4e0d\u662f\u7b80\u5355\u5730\u8ba9\u5730\u5740 +1<\/code>\u3002<\/p>\n\n\n\n
\u800c\u662f\uff1a<\/p>\n\n\n\n
1000 + sizeof(int)<\/code><\/pre>\n\n\n\n
\u4e5f\u5c31\u662f\uff1a<\/p>\n\n\n\n
1000 + 4 = 1004<\/code><\/pre>\n\n\n\n
\u6240\u4ee5\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5c31\u4f1a\u5f97\u5230\uff1a<\/p>\n\n\n\n
20<\/code><\/pre>\n\n\n\n
\u518d\u6267\u884c\uff1a<\/p>\n\n\n\n
<\/a>p++;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5c31\u4f1a\u79fb\u52a8\u5230 a[2]<\/code>\uff1a<\/p>\n\n\n\n
1008<\/code><\/pre>\n\n\n\n
\u4e8e\u662f\uff1a<\/p>\n\n\n\n
<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5f97\u5230\uff1a<\/p>\n\n\n\n
30<\/code><\/pre>\n\n\n\n
\n\n\n\n
\u4e0d\u540c\u7c7b\u578b\u7684\u6307\u9488<\/h2>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>char<\/span> *<\/span>cp;<\/span><\/span>\n<\/a>int<\/span> *<\/span>ip;<\/span><\/span>\n<\/a>double<\/span> *<\/span>dp;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u5047\u8bbe\uff1a<\/p>\n\n\n\n
sizeof(char)   = 1\nsizeof(int)    = 4\nsizeof(double) = 8<\/code><\/pre>\n\n\n\n
\u90a3\u4e48\uff1a<\/p>\n\n\n\n
cp++  \u2192 \u5730\u5740\u589e\u52a0 1\nip++  \u2192 \u5730\u5740\u589e\u52a0 4\ndp++  \u2192 \u5730\u5740\u589e\u52a0 8<\/code><\/pre>\n\n\n\n
\u6240\u4ee5\u6307\u9488\u7684\u7c7b\u578b\u4e0d\u4ec5\u4ec5\u662f\u4e3a\u4e86\u533a\u5206\u6570\u636e\u7c7b\u578b\uff0c\u4e5f\u4f1a\u5f71\u54cd\u6307\u9488\u8fd0\u7b97<\/strong>\u3002<\/p>\n\n\n\n
\n\n\n\n
\u6307\u9488\u7c7b\u578b\u7684\u672c\u8d28<\/h2>\n\n\n\n
\u53ef\u4ee5\u7b80\u5355\u8bb0\u6210\uff1a<\/p>\n\n\n\n
int *p\n   \u2502\n   \u251c\u2500 p \u4fdd\u5b58\u4e00\u4e2a\u5730\u5740\n   \u2502\n   \u2514\u2500 int \u8868\u793a\u8fd9\u4e2a\u5730\u5740\u5bf9\u5e94\u7684\u6570\u636e\u6309\u7167 int \u7c7b\u578b\u5904\u7406<\/code><\/pre>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n
\n
p<\/code> \u662f\u4e00\u4e2a\u6307\u5411 int<\/code> \u7c7b\u578b\u6570\u636e\u7684\u6307\u9488\u3002<\/p>\n<\/blockquote>\n\n\n\n
<\/a>char<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n
\n
p<\/code> \u662f\u4e00\u4e2a\u6307\u5411 char<\/code> \u7c7b\u578b\u6570\u636e\u7684\u6307\u9488\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u8bb0\u4f4f\uff1a<\/strong><\/p>\n\n\n\n
\u6307\u9488\u4fdd\u5b58\u5730\u5740\n\u6307\u9488\u7c7b\u578b\u51b3\u5b9a\u5982\u4f55\u89e3\u91ca\u5730\u5740\u4e2d\u7684\u6570\u636e\n\u6307\u9488\u7c7b\u578b\u8fd8\u51b3\u5b9a\u6307\u9488\u8fd0\u7b97\u65f6\u79fb\u52a8\u591a\u5c11\u5b57\u8282<\/code><\/pre>\n\n\n\n
NULL \u7a7a\u6307\u9488<\/h2>\n\n\n\n
\u6709\u65f6\u5019\u6211\u4eec\u521b\u5efa\u4e86\u4e00\u4e2a\u6307\u9488\uff0c\u4f46\u662f\u6682\u65f6\u4e0d\u8ba9\u5b83\u6307\u5411\u4efb\u4f55\u6570\u636e\u3002<\/p>\n\n\n\n
\u8fd9\u65f6\u5019\u53ef\u4ee5\u8ba9\u6307\u9488\u4fdd\u5b58\u4e00\u4e2a\u7a7a\u6307\u9488\u503c<\/strong>\u3002<\/p>\n\n\n\n
\u901a\u5e38\u4f7f\u7528\uff1a<\/p>\n\n\n\n
<\/a>NULL<\/span><\/code><\/pre><\/div>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p =<\/span> NULL;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\uff1a<\/p>\n\n\n\n
\n
\u521b\u5efa\u4e00\u4e2a int<\/code> \u7c7b\u578b\u7684\u6307\u9488 p<\/code>\uff0c\u4f46\u73b0\u5728\np<\/code> \u4e0d\u6307\u5411\u4efb\u4f55\u6709\u6548\u7684\u5bf9\u8c61\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u4e3a\uff1a<\/p>\n\n\n\n
p\n\u2502\n\u25bc\nNULL\n\u2502\n\u2514\u2500\u2500 \u4e0d\u6307\u5411\u4efb\u4f55\u6709\u6548\u6570\u636e<\/code><\/pre>\n\n\n\n
\n\n\n\n
\u4e3a\u4ec0\u4e48\u9700\u8981 NULL\uff1f<\/h3>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u91cc\u7684 p<\/code> \u6ca1\u6709\u521d\u59cb\u5316\u3002<\/p>\n\n\n\n
\u5b83\u91cc\u9762\u53ef\u80fd\u4fdd\u5b58\u4e00\u4e2a\u672a\u77e5\u7684\u5730\u5740\uff0c\u8fd9\u79cd\u6307\u9488\u4e0d\u80fd\u76f4\u63a5\u4f7f\u7528\u3002<\/p>\n\n\n\n
\u800c\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p =<\/span> NULL;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u660e\u786e\u8868\u793a\uff1a<\/p>\n\n\n\n
\n
p<\/code> \u5f53\u524d\u6ca1\u6709\u6307\u5411\u4efb\u4f55\u5bf9\u8c61\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u8fd9\u6837\u6211\u4eec\u5c31\u53ef\u4ee5\u5728\u4f7f\u7528\u6307\u9488\u4e4b\u524d\u8fdb\u884c\u5224\u65ad\uff1a<\/p>\n\n\n\n
<\/a>if<\/span> (<\/span>p !=<\/span> NULL)<\/span> {<\/span><\/span>\n<\/a>    printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span>\n<\/a>}<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ea\u6709\u5f53 p<\/code> \u4e0d\u4e3a\u7a7a\u65f6\uff0c\u624d\u901a\u8fc7 *p<\/code> \u8bbf\u95ee\u6570\u636e\u3002<\/p>\n\n\n\n
\n\n\n\n
NULL \u6307\u9488\u4e0d\u80fd\u89e3\u5f15\u7528<\/h3>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p =<\/span> NULL;<\/span><\/span>\n<\/a><\/span>\n<\/a>printf(<\/span>\"<\/span>%d\\n<\/span>\"<\/span>,<\/span> *<\/span>p);<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u662f\u9519\u8bef\u7684\u3002<\/p>\n\n\n\n
\u56e0\u4e3a\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u8868\u793a\uff1a<\/p>\n\n\n\n
\n
\u8bbf\u95ee p<\/code> \u6240\u6307\u5411\u7684\u6570\u636e\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u4f46\u662f p<\/code> \u6839\u672c\u6ca1\u6709\u6307\u5411\u6709\u6548\u7684\u6570\u636e\u3002<\/p>\n\n\n\n
\u6240\u4ee5\uff1a<\/p>\n\n\n\n
p = NULL\n   \u2193\n\u6ca1\u6709\u6307\u5411\u6709\u6548\u5bf9\u8c61\n   \u2193\n*p\n   \u2193\n\u9519\u8bef<\/code><\/pre>\n\n\n\n
\u53ef\u80fd\u5bfc\u81f4\u7a0b\u5e8f\u5d29\u6e83\u6216\u4ea7\u751f\u672a\u5b9a\u4e49\u884c\u4e3a\u3002<\/p>\n\n\n\n
\n\n\n\n
\u5224\u65ad\u6307\u9488\u662f\u5426\u4e3a\u7a7a<\/h3>\n\n\n\n
\u53ef\u4ee5\u4f7f\u7528\uff1a<\/p>\n\n\n\n
<\/a>if<\/span> (<\/span>p ==<\/span> NULL)<\/span> {<\/span><\/span>\n<\/a>    printf(<\/span>\"p\u662f\u7a7a\u6307\u9488<\/span>\\n<\/span>\"<\/span>);<\/span><\/span>\n<\/a>}<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u4e5f\u53ef\u4ee5\u5199\u6210\uff1a<\/p>\n\n\n\n
<\/a>if<\/span> (<\/span>p)<\/span> {<\/span><\/span>\n<\/a>    printf(<\/span>\"p\u4e0d\u662f\u7a7a\u6307\u9488<\/span>\\n<\/span>\"<\/span>);<\/span><\/span>\n<\/a>}<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u6216\u8005\uff1a<\/p>\n\n\n\n
<\/a>if<\/span> (!<\/span>p)<\/span> {<\/span><\/span>\n<\/a>    printf(<\/span>\"p\u662f\u7a7a\u6307\u9488<\/span>\\n<\/span>\"<\/span>);<\/span><\/span>\n<\/a>}<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u521d\u5b66\u9636\u6bb5\u63a8\u8350\u4f7f\u7528\u7b2c\u4e00\u79cd\uff1a<\/p>\n\n\n\n
<\/a>if<\/span> (<\/span>p ==<\/span> NULL)<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u8bfb\u6027\u66f4\u597d\u3002<\/p>\n\n\n\n
\n\n\n\n
NULL \u548c\u666e\u901a\u5730\u5740<\/h3>\n\n\n\n
\u4f8b\u5982\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> a =<\/span> 10<\/span>;<\/span><\/span>\n<\/a><\/span>\n<\/a>int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span><\/span>\n<\/a>int<\/span> *<\/span>q =<\/span> NULL;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u7406\u89e3\u6210\uff1a<\/p>\n\n\n\n
p\n\u2502\n\u25bc\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502   10    \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518\n    a\n\n\nq\n\u2502\n\u25bc\nNULL\n\n\u4e0d\u6307\u5411\u4efb\u4f55\u6709\u6548\u5bf9\u8c61<\/code><\/pre>\n\n\n\n
\u56e0\u6b64\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>p<\/span><\/code><\/pre><\/div>\n\n\n\n
\u53ef\u4ee5\u8bbf\u95ee a<\/code>\uff1a<\/p>\n\n\n\n
*p \u2192 10<\/code><\/pre>\n\n\n\n
\u800c\uff1a<\/p>\n\n\n\n
<\/a>*<\/span>q<\/span><\/code><\/pre><\/div>\n\n\n\n
\u4e0d\u80fd\u8bbf\u95ee\u6570\u636e\uff0c\u56e0\u4e3a q<\/code> \u662f\u7a7a\u6307\u9488\u3002<\/p>\n\n\n\n
\n\n\n\n
NULL \u548c\u672a\u521d\u59cb\u5316\u6307\u9488\u7684\u533a\u522b<\/h3>\n\n\n\n
\u8fd9\u662f\u975e\u5e38\u91cd\u8981\u7684\u533a\u522b\u3002<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u662f\u672a\u521d\u59cb\u5316\u6307\u9488<\/strong>\u3002<\/p>\n\n\n\n
\u5b83\u91cc\u9762\u7684\u503c\u662f\u4e0d\u786e\u5b9a\u7684\u3002<\/p>\n\n\n\n
\u800c\uff1a<\/p>\n\n\n\n
<\/a>int<\/span> *<\/span>p =<\/span> NULL;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n
\u8fd9\u662f\u7a7a\u6307\u9488<\/strong>\u3002<\/p>\n\n\n\n
\u5b83\u660e\u786e\u8868\u793a\uff1a<\/p>\n\n\n\n
\n
\u5f53\u524d\u4e0d\u6307\u5411\u4efb\u4f55\u6709\u6548\u5bf9\u8c61\u3002<\/p>\n<\/blockquote>\n\n\n\n
\u53ef\u4ee5\u8bb0\u6210\uff1a<\/p>\n\n\n\n
int *p;\n    \u2193\n\u672a\u521d\u59cb\u5316\n    \u2193\n\u4e0d\u8981\u4f7f\u7528\n\n\nint *p = NULL;\n        \u2193\n\u660e\u786e\u8868\u793a\u6ca1\u6709\u6307\u5411\u5bf9\u8c61\n        \u2193\n\u53ef\u4ee5\u8fdb\u884c NULL \u5224\u65ad<\/code><\/pre>\n\n\n\n
\u8bb0\u4f4f\uff1a<\/strong><\/p>\n\n\n\n
NULL\n \u2193\n\u7a7a\u6307\u9488\n \u2193\n\u4e0d\u6307\u5411\u4efb\u4f55\u6709\u6548\u5bf9\u8c61\n \u2193\n\u4e0d\u80fd\u89e3\u5f15\u7528<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u901a\u8fc7\u6307\u9488\uff0c\u53ef\u4ee5\u7b80\u5316\u4e00\u4e9b C \u7f16\u7a0b\u4efb\u52a1\u7684\u6267\u884c\uff0c\u8fd8\u6709\u4e00\u4e9b\u4efb\u52a1\uff0c\u5982\u52a8\u6001\u5185\u5b58\u5206\u914d\uff0c\u6ca1\u6709\u6307\u9488\u662f\u65e0\u6cd5\u6267\u884c\u7684\u3002\u6240\u4ee5\uff0c\u60f3\u8981\u6210\u4e3a\u4e00\u540d\u4f18\u79c0\u7684 C \u7a0b\u5e8f …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"emotion":"","emotion_color":"","title_style":"","license":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-82","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=\/wp\/v2\/posts\/82","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=82"}],"version-history":[{"count":1,"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=\/wp\/v2\/posts\/82\/revisions"}],"predecessor-version":[{"id":83,"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=\/wp\/v2\/posts\/82\/revisions\/83"}],"wp:attachment":[{"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=82"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=82"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/decagrammaton.xyz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=82"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}