{"id":1054782,"date":"2024-12-31T14:45:11","date_gmt":"2024-12-31T06:45:11","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1054782.html"},"modified":"2024-12-31T14:45:14","modified_gmt":"2024-12-31T06:45:14","slug":"python%e4%b8%ad%e5%a6%82%e4%bd%95%e8%a1%a8%e8%be%be2%e7%9a%84n%e6%ac%a1%e6%96%b9","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1054782.html","title":{"rendered":"python\u4e2d\u5982\u4f55\u8868\u8fbe2\u7684n\u6b21\u65b9"},"content":{"rendered":"

\"python\u4e2d\u5982\u4f55\u8868\u8fbe2\u7684n\u6b21\u65b9\"<\/p>\n

Python\u4e2d\u8868\u8fbe2\u7684n\u6b21\u65b9\u53ef\u4ee5\u4f7f\u7528\u51e0\u79cd\u4e0d\u540c\u7684\u65b9\u6cd5\uff1a\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26<\/strong><\/code>\u3001\u4f7f\u7528\u5185\u7f6e\u51fd\u6570pow()<\/code>\u3001\u4f7f\u7528\u4f4d\u8fd0\u7b97\u3002 \u5728\u8fd9\u91cc\u6211\u4eec\u91cd\u70b9\u4ecb\u7ecd\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26\u6765\u8868\u8fbe2\u7684n\u6b21\u65b9\u3002\u5e42\u8fd0\u7b97\u7b26<\/strong><\/code>\u662fPython\u4e2d\u7528\u4e8e\u8ba1\u7b97\u4e00\u4e2a\u6570\u7684\u6307\u6570\u6b21\u5e42\u7684\u8fd0\u7b97\u7b26\u3002\u4f8b\u5982\uff0c2 n<\/code>\u8868\u793a2\u7684n\u6b21\u65b9\u3002<\/p>\n<\/p>\n

\u4e00\u3001\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26<\/code><\/h2>\n<\/p>\n

\u5e42\u8fd0\u7b97\u7b26<strong><\/code>\u662fPython\u4e2d\u6700\u5e38\u89c1\u3001\u6700\u76f4\u63a5\u7684\u65b9\u5f0f\u6765\u8ba1\u7b972\u7684n\u6b21\u65b9\u3002\u5b83\u7684\u8bed\u6cd5\u7b80\u5355\uff0c\u6613\u4e8e\u7406\u89e3\u5e76\u4e14\u975e\u5e38\u76f4\u89c2\u3002\u4e3e\u4e2a\u4f8b\u5b50\uff0c\u5982\u679c\u4f60\u60f3\u8ba1\u7b972\u76843\u6b21\u65b9\uff0c\u4f60\u53ef\u4ee5\u8fd9\u6837\u5199\uff1a2 <\/strong> 3<\/code>\uff0c\u7ed3\u679c\u4e3a8\u3002\u5e42\u8fd0\u7b97\u7b26\u7684\u8ba1\u7b97\u901f\u5ea6\u975e\u5e38\u5feb\uff0c\u56e0\u4e3a\u5b83\u662fPython\u8bed\u8a00\u672c\u8eab\u63d0\u4f9b\u7684\u57fa\u7840\u529f\u80fd\u3002<\/p>\n<\/p>\n

\u4ee3\u7801\u793a\u4f8b<\/h3>\n<\/p>\n

n = 3<\/p>\n
result = 2  n<\/p>\n
print("2\u7684", n, "\u6b21\u65b9\u662f\uff1a", result)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c2  n<\/code>\u8ba1\u7b97\u4e862\u7684n\u6b21\u65b9\uff0c\u5e76\u5c06\u7ed3\u679c\u5b58\u50a8\u5728\u53d8\u91cfresult<\/code>\u4e2d\uff0c\u6700\u540e\u901a\u8fc7print<\/code>\u51fd\u6570\u8f93\u51fa\u7ed3\u679c\u3002<\/p>\n<\/p>\n
\u4e8c\u3001\u4f7f\u7528\u5185\u7f6e\u51fd\u6570pow()<\/code><\/h2>\n<\/p>\n
Python\u63d0\u4f9b\u4e86\u4e00\u4e2a\u5185\u7f6e\u51fd\u6570pow(x, y)<\/code>\uff0c\u7528\u4e8e\u8ba1\u7b97x\u7684y\u6b21\u65b9\u3002\u4e0e\u5e42\u8fd0\u7b97\u7b26<\/code>\u76f8\u6bd4\uff0cpow()<\/code>\u51fd\u6570\u66f4\u52a0\u7075\u6d3b\uff0c\u56e0\u4e3a\u5b83\u5141\u8bb8\u4f20\u9012\u4e09\u4e2a\u53c2\u6570\uff0c\u5176\u4e2d\u7b2c\u4e09\u4e2a\u53c2\u6570\u662f\u4e00\u4e2a\u53ef\u9009\u7684\u53d6\u6a21\u503c\uff0c\u7528\u4e8e\u8ba1\u7b97\u7ed3\u679c\u5bf9\u8be5\u503c\u53d6\u6a21\u540e\u7684\u7ed3\u679c\u3002<\/p>\n<\/p>\n
\u4ee3\u7801\u793a\u4f8b<\/h3>\n<\/p>\n
n = 3<\/p>\n
result = pow(2, n)<\/p>\n
print("2\u7684", n, "\u6b21\u65b9\u662f\uff1a", result)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0cpow(2, n)<\/code>\u8ba1\u7b97\u4e862\u7684n\u6b21\u65b9\uff0c\u5e76\u5c06\u7ed3\u679c\u5b58\u50a8\u5728\u53d8\u91cfresult<\/code>\u4e2d\uff0c\u6700\u540e\u901a\u8fc7print<\/code>\u51fd\u6570\u8f93\u51fa\u7ed3\u679c\u3002<\/p>\n<\/p>\n
\u4e09\u3001\u4f7f\u7528\u4f4d\u8fd0\u7b97<\/h2>\n<\/p>\n
\u4f4d\u8fd0\u7b97\u662f\u4e00\u79cd\u66f4\u5e95\u5c42\u3001\u66f4\u9ad8\u6548\u7684\u8ba1\u7b97\u65b9\u5f0f\u3002\u5bf9\u4e8e2\u7684n\u6b21\u65b9\uff0c\u53ef\u4ee5\u901a\u8fc7\u5de6\u79fb\u4f4d\u64cd\u4f5c\u6765\u5b9e\u73b0\u3002\u5de6\u79fb\u4f4d\u64cd\u4f5c\u7b26<<<\/code>\u5c06\u4e00\u4e2a\u6574\u6570\u7684\u4e8c\u8fdb\u5236\u4f4d\u5411\u5de6\u79fb\u52a8\u6307\u5b9a\u7684\u4f4d\u6570\uff0c\u76f8\u5f53\u4e8e\u4e58\u4ee52\u7684n\u6b21\u65b9\u3002<\/p>\n<\/p>\n
\u4ee3\u7801\u793a\u4f8b<\/h3>\n<\/p>\n
n = 3<\/p>\n
result = 1 << n<\/p>\n
print("2\u7684", n, "\u6b21\u65b9\u662f\uff1a", result)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c1 << n<\/code>\u5c06\u6574\u65701\u7684\u4e8c\u8fdb\u5236\u4f4d\u5411\u5de6\u79fb\u52a8n\u4f4d\uff0c\u76f8\u5f53\u4e8e\u8ba1\u7b97\u4e862\u7684n\u6b21\u65b9\uff0c\u5e76\u5c06\u7ed3\u679c\u5b58\u50a8\u5728\u53d8\u91cfresult<\/code>\u4e2d\uff0c\u6700\u540e\u901a\u8fc7print<\/code>\u51fd\u6570\u8f93\u51fa\u7ed3\u679c\u3002<\/p>\n<\/p>\n
\u56db\u3001\u6027\u80fd\u5bf9\u6bd4<\/h2>\n<\/p>\n
\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u9009\u62e9\u54ea\u79cd\u65b9\u5f0f\u8ba1\u7b972\u7684n\u6b21\u65b9\u53d6\u51b3\u4e8e\u5177\u4f53\u60c5\u51b5\u3002\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26<\/code>\u662f\u6700\u65b9\u4fbf\u7684\u9009\u62e9\uff0c\u56e0\u4e3a\u5b83\u7684\u8bed\u6cd5\u7b80\u5355\u4e14\u6613\u4e8e\u7406\u89e3\u3002\u4f46\u5728\u67d0\u4e9b\u5bf9\u6027\u80fd\u8981\u6c42\u8f83\u9ad8\u7684\u573a\u666f\u4e0b\uff0c\u4f7f\u7528\u4f4d\u8fd0\u7b97\u53ef\u80fd\u4f1a\u66f4\u9ad8\u6548\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u7b80\u5355\u7684\u6027\u80fd\u6bd4\u8f83\u793a\u4f8b\uff1a<\/p>\n<\/p>\n
\u4ee3\u7801\u793a\u4f8b<\/h3>\n<\/p>\n
import time<\/p>\n
n = 20<\/p>\n
\u6d4b\u8bd5\u5e42\u8fd0\u7b97\u7b26<\/strong><\/h2>\n
start_time = time.time()<\/p>\n
result = 2  n<\/p>\n
end_time = time.time()<\/p>\n
print("\u5e42\u8fd0\u7b97\u7b26\u8ba1\u7b97\u7ed3\u679c\uff1a", result, "\uff0c\u8017\u65f6\uff1a", end_time - start_time)<\/p>\n
\u6d4b\u8bd5\u5185\u7f6e\u51fd\u6570pow()<\/strong><\/h2>\n
start_time = time.time()<\/p>\n
result = pow(2, n)<\/p>\n
end_time = time.time()<\/p>\n
print("\u5185\u7f6e\u51fd\u6570pow\u8ba1\u7b97\u7ed3\u679c\uff1a", result, "\uff0c\u8017\u65f6\uff1a", end_time - start_time)<\/p>\n
\u6d4b\u8bd5\u4f4d\u8fd0\u7b97<\/strong><\/h2>\n
start_time = time.time()<\/p>\n
result = 1 << n<\/p>\n
end_time = time.time()<\/p>\n
print("\u4f4d\u8fd0\u7b97\u8ba1\u7b97\u7ed3\u679c\uff1a", result, "\uff0c\u8017\u65f6\uff1a", end_time - start_time)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u901a\u8fc7\u4e0a\u8ff0\u4ee3\u7801\uff0c\u4f60\u53ef\u4ee5\u6bd4\u8f83\u4e0d\u540c\u65b9\u6cd5\u7684\u8ba1\u7b97\u65f6\u95f4\uff0c\u9009\u62e9\u6700\u9002\u5408\u4f60\u9700\u6c42\u7684\u65b9\u6cd5\u3002<\/p>\n<\/p>\n
\u4e94\u3001\u5b9e\u9645\u5e94\u7528<\/h2>\n<\/p>\n
\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u8ba1\u7b972\u7684n\u6b21\u65b9\u7684\u9700\u6c42\u975e\u5e38\u5e38\u89c1\uff0c\u5c24\u5176\u662f\u5728\u8ba1\u7b97\u673a\u79d1\u5b66\u548c\u5de5\u7a0b\u9886\u57df\u3002\u4f8b\u5982\uff0c\u5728\u6570\u636e\u52a0\u5bc6\u3001\u56fe\u50cf\u5904\u7406\u3001\u4fe1\u53f7\u5904\u7406\u7b49\u9886\u57df\uff0c\u7ecf\u5e38\u9700\u8981\u8fdb\u884c\u5927\u89c4\u6a21\u7684\u5e42\u8fd0\u7b97\u3002\u5728\u8fd9\u4e9b\u573a\u666f\u4e2d\uff0c\u9009\u62e9\u5408\u9002\u7684\u8ba1\u7b97\u65b9\u6cd5\u663e\u5f97\u5c24\u4e3a\u91cd\u8981\u3002<\/p>\n<\/p>\n
\u793a\u4f8b\u5e94\u7528\uff1a\u8ba1\u7b97\u673a\u7f51\u7edc\u4e2d\u7684\u5b50\u7f51\u5212\u5206<\/h3>\n<\/p>\n
\u5728\u8ba1\u7b97\u673a\u7f51\u7edc\u4e2d\uff0c\u5b50\u7f51\u5212\u5206\u662f\u4e00\u4e2a\u5e38\u89c1\u7684\u5e94\u7528\u573a\u666f\u3002\u5b50\u7f51\u63a9\u7801\u901a\u5e38\u8868\u793a\u4e3a2\u7684n\u6b21\u65b9\u51cf1\u3002\u4f8b\u5982\uff0c\u5bf9\u4e8e\u4e00\u4e2a\u5b50\u7f51\u63a9\u7801255.255.255.0\uff0c\u5b83\u53ef\u4ee5\u8868\u793a\u4e3a2\u768424\u6b21\u65b9\u51cf1\u3002<\/p>\n<\/p>\n
n = 24<\/p>\n
subnet_mask = (1 << n) - 1<\/p>\n
print("\u5b50\u7f51\u63a9\u7801\u662f\uff1a", subnet_mask)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c(1 << n) - 1<\/code>\u8ba1\u7b97\u4e862\u768424\u6b21\u65b9\u51cf1\uff0c\u5e76\u5c06\u7ed3\u679c\u5b58\u50a8\u5728\u53d8\u91cfsubnet_mask<\/code>\u4e2d\uff0c\u6700\u540e\u901a\u8fc7print<\/code>\u51fd\u6570\u8f93\u51fa\u7ed3\u679c\u3002<\/p>\n<\/p>\n
\u793a\u4f8b\u5e94\u7528\uff1a\u56fe\u50cf\u5904\u7406\u4e2d\u7684\u50cf\u7d20\u503c\u8ba1\u7b97<\/h3>\n<\/p>\n
\u5728\u56fe\u50cf\u5904\u7406\u9886\u57df\uff0c\u50cf\u7d20\u503c\u7684\u8ba1\u7b97\u4e5f\u7ecf\u5e38\u9700\u8981\u4f7f\u75282\u7684n\u6b21\u65b9\u3002\u4f8b\u5982\uff0c\u5728\u7070\u5ea6\u56fe\u50cf\u4e2d\uff0c\u6bcf\u4e2a\u50cf\u7d20\u503c\u7684\u8303\u56f4\u662f0\u52302\u76848\u6b21\u65b9\u51cf1\uff0c\u53730\u5230255\u3002<\/p>\n<\/p>\n
n = 8<\/p>\n
max_pixel_value = (1 << n) - 1<\/p>\n
print("\u7070\u5ea6\u56fe\u50cf\u7684\u6700\u5927\u50cf\u7d20\u503c\u662f\uff1a", max_pixel_value)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c(1 << n) - 1<\/code>\u8ba1\u7b97\u4e862\u76848\u6b21\u65b9\u51cf1\uff0c\u5e76\u5c06\u7ed3\u679c\u5b58\u50a8\u5728\u53d8\u91cfmax_pixel_value<\/code>\u4e2d\uff0c\u6700\u540e\u901a\u8fc7print<\/code>\u51fd\u6570\u8f93\u51fa\u7ed3\u679c\u3002<\/p>\n<\/p>\n
\u603b\u7ed3<\/h2>\n<\/p>\n
\u901a\u8fc7\u672c\u6587\u7684\u4ecb\u7ecd\uff0c\u4f60\u5e94\u8be5\u5df2\u7ecf\u638c\u63e1\u4e86Python\u4e2d\u8868\u8fbe2\u7684n\u6b21\u65b9\u7684\u51e0\u79cd\u65b9\u6cd5\uff1a\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26<strong><\/code>\u3001\u4f7f\u7528\u5185\u7f6e\u51fd\u6570pow()<\/code>\u3001\u4f7f\u7528\u4f4d\u8fd0\u7b97\u3002\u6bcf\u79cd\u65b9\u6cd5\u90fd\u6709\u5176\u4f18\u7f3a\u70b9\uff0c\u5177\u4f53\u9009\u62e9\u54ea\u79cd\u65b9\u6cd5\u53d6\u51b3\u4e8e\u4f60\u7684\u5b9e\u9645\u9700\u6c42\u3002\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26<\/strong><\/code>\u662f\u6700\u65b9\u4fbf\u7684\u9009\u62e9\uff0c\u800c\u5728\u5bf9\u6027\u80fd\u8981\u6c42\u8f83\u9ad8\u7684\u573a\u666f\u4e0b\uff0c\u4f7f\u7528\u4f4d\u8fd0\u7b97\u53ef\u80fd\u4f1a\u66f4\u9ad8\u6548\u3002\u5e0c\u671b\u672c\u6587\u5bf9\u4f60\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\u8ba1\u7b972\u7684n\u6b21\u65b9\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n<\/p>\n
\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
 \u5982\u4f55\u5728Python\u4e2d\u8ba1\u7b972\u7684n\u6b21\u65b9\uff1f<\/strong>
\u5728Python\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26\u201c\u201d\u6765\u8ba1\u7b972\u7684n\u6b21\u65b9\uff0c\u4f8b\u5982\uff0c\u8868\u8fbe\u5f0f2 <\/strong> n<\/code>\u5c06\u8fd4\u56de2\u7684n\u6b21\u65b9\u3002\u60a8\u53ea\u9700\u5c06n\u66ff\u6362\u4e3a\u6240\u9700\u7684\u6574\u6570\u503c\u5373\u53ef\u3002\u4f8b\u5982\uff0cresult = 2 ** 5<\/code>\u5c06\u8ba1\u7b972\u76845\u6b21\u65b9\uff0c\u7ed3\u679c\u4e3a32\u3002<\/p>\n
\u5728Python\u4e2d\u8fd8\u6709\u54ea\u4e9b\u65b9\u6cd5\u53ef\u4ee5\u8ba1\u7b97\u5e42\uff1f<\/strong>
\u9664\u4e86\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26\u201c**\u201d\uff0cPython\u8fd8\u63d0\u4f9b\u4e86\u5185\u7f6e\u51fd\u6570pow()<\/code>\uff0c\u60a8\u53ef\u4ee5\u901a\u8fc7pow(2, n)<\/code>\u6765\u8ba1\u7b972\u7684n\u6b21\u65b9\u3002\u8fd9\u4e2a\u51fd\u6570\u7684\u4f18\u52bf\u5728\u4e8e\u5b83\u8fd8\u53ef\u4ee5\u63a5\u6536\u4e00\u4e2a\u53ef\u9009\u7684\u6a21\u53c2\u6570\uff0c\u4ece\u800c\u5728\u8ba1\u7b97\u8fc7\u7a0b\u4e2d\u8fdb\u884c\u6a21\u8fd0\u7b97\u3002<\/p>\n
\u5982\u4f55\u5728Python\u4e2d\u5904\u7406\u5927\u6570\u76842\u7684n\u6b21\u65b9\uff1f<\/strong>
Python\u7684\u6574\u6570\u7c7b\u578b\u80fd\u591f\u5904\u7406\u4efb\u610f\u5927\u5c0f\u7684\u6570\u5b57\uff0c\u56e0\u6b64\u8ba1\u7b97\u975e\u5e38\u5927\u76842\u7684n\u6b21\u65b9\u4e0d\u4f1a\u5f15\u53d1\u6ea2\u51fa\u95ee\u9898\u3002\u4f8b\u5982\uff0c2 ** 1000<\/code>\u53ef\u4ee5\u987a\u5229\u8ba1\u7b97\u51fa\u4e00\u4e2a\u975e\u5e38\u5927\u7684\u6570\u5b57\u3002\u4e3a\u4e86\u66f4\u597d\u5730\u7ba1\u7406\u548c\u663e\u793a\u8fd9\u4e9b\u5927\u6570\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u5b57\u7b26\u4e32\u683c\u5f0f\u5316\u65b9\u6cd5\u6216format()<\/code>\u51fd\u6570\u6765\u63a7\u5236\u8f93\u51fa\u683c\u5f0f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"Python\u4e2d\u8868\u8fbe2\u7684n\u6b21\u65b9\u53ef\u4ee5\u4f7f\u7528\u51e0\u79cd\u4e0d\u540c\u7684\u65b9\u6cd5\uff1a\u4f7f\u7528\u5e42\u8fd0\u7b97\u7b26<\/strong>\u3001\u4f7f\u7528\u5185\u7f6e\u51fd\u6570p […]","protected":false},"author":3,"featured_media":1054787,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1054782"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=1054782"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1054782\/revisions"}],"predecessor-version":[{"id":1054788,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1054782\/revisions\/1054788"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/1054787"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=1054782"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=1054782"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=1054782"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}