{"id":198,"date":"2015-04-04T14:37:34","date_gmt":"2015-04-04T06:37:34","guid":{"rendered":"http:\/\/sqrt-1.me\/?p=198"},"modified":"2016-11-19T14:46:21","modified_gmt":"2016-11-19T06:46:21","slug":"%e4%b8%ba%e4%bb%80%e4%b9%88c%e7%9b%b4%e6%8e%a5%e8%be%93%e5%87%ba2100%e5%8f%af%e4%bb%a5%e7%b2%be%e7%a1%ae%e5%88%b0%e4%b8%aa%e4%bd%8d","status":"publish","type":"post","link":"https:\/\/sqrt-1.me\/?p=198","title":{"rendered":"\u4e3a\u4ec0\u4e48C++\u76f4\u63a5\u8f93\u51fa21000<\/sup>\u53ef\u4ee5\u7cbe\u786e\u5230\u4e2a\u4f4d"},"content":{"rendered":"

\u8fd9\u4e2a\u60f3\u6cd5\u6e90\u4e8e\u4e00\u9053\u7a0b\u5e8f\u8bbe\u8ba1\u8bfe\u7684\u4e0a\u673a\u9898\uff1a\u4efb\u610f\u7ed9\u5b9a\u4e00\u4e2a\u6b63\u6574\u6570N(N<=100)\uff0c\u8ba1\u7b972\u7684n\u6b21\u65b9\u7684\u503c\u3002\n\n\u8fd9\u9053\u9898\u7684\u672c\u610f\u662f\u7ec3\u4e60\u9ad8\u7cbe\u5ea6\u8ba1\u7b97\uff0c\u4f46\u662f\u53ef\u4ee5\u53d1\u73b0\uff0c\u4f7f\u7528long double\u7c7b\u578b\u8c03\u7528pow\u51fd\u6570\u5c31\u8db3\u591f\u4e86\u3002\u5f53\u7136\u6211\u8fd8\u662f\u7528\u9ad8\u7cbe\u5ea6\u8ba1\u7b97\u5199\u7684\u3002\n\n\u7136\u800c\uff0c\u6211\u53d1\u73b0\u5373\u4f7f\u4ec5\u4f7f\u7528double\uff0c\u751a\u81f3\u7528float\uff0c\u5728C++\u4e2d\u90fd\u53ef\u4ee5\u8f93\u51fa\u6b63\u786e\u7684\u7b54\u6848\u3002\n\n\u8fd0\u884c\u4e0b\u9762\u7684C++\u4ee3\u7801\uff1a\n\n\n\n

\r\n#include<iostream>\r\n#include<cmath>\r\n\r\nusing namespace std;\r\n\r\nint main(){\r\n    int x;\r\n    cin>>x;\r\n    cout.precision(0);\r\n    cout<<fixed<<pow(2,x);\r\n    return 0;\r\n}\r\n<\/pre>\n
\u8f93\u51651000\uff0c\u7a0b\u5e8f\u8f93\u51fa\u4e00\u4e2a\u8d85\u8fc7300\u4f4d\u7684\u7ed3\u679c\uff0c\u867d\u7136\u8fd9\u65e9\u5df2\u8d85\u51fadouble\u548clong double\u7684\u7cbe\u5ea6\uff0c\u4f46\u662f\u8fd0\u7b97\u7ed3\u679c\u662f\u5b8c\u5168\u6b63\u786e\u7684\u3002<\/p>\n
\u81f3\u4e8e\u7ed3\u679c\u7684\u6b63\u786e\u6027\uff0c\u6bd4\u8f83\u65b9\u4fbf\u7684\u65b9\u6cd5\u5c31\u662f\u4e0ePython\u7ed9\u51fa\u7684\u7ed3\u679c\u8fdb\u884c\u5bf9\u6bd4\u3002\u5728Python\u7684\u63a7\u5236\u53f0\u4e2d\u8f93\u51652**1000\u53ef\u4ee5\u76f4\u63a5\u5f97\u5230\u9ad8\u7cbe\u5ea6\u8ba1\u7b97\u7684\u7ed3\u679c\uff0c\u5f88\u65b9\u4fbf\u3002<\/p>\n
\u4e3a\u4ec0\u4e48\u7ed3\u679c\u662f\u7cbe\u786e\u7684\u5462\uff1f<\/p>\n
<\/p>\n
\u6211\u5c1d\u8bd5\u7528\u540c\u6837\u7684\u65b9\u6cd5\u8ba1\u7b973\u7684n\u6b21\u65b9\uff0c\u53d1\u73b0\u53ea\u6709\u524d\u51e0\u4f4d\u662f\u6b63\u786e\u7684\uff0c\u800c\u4e14\u6700\u540e\u4e00\u4f4d\u6570\u662f\u5076\u6570\u3002<\/p>\n
\u8fd9\u6837\u539f\u56e0\u5c31\u5f88\u663e\u7136\u4e86\uff1a\u548c\u8ba1\u7b97\u673a\u4e2d\u6d6e\u70b9\u6570\u7684\u8868\u793a\u65b9\u6cd5\u6709\u5173\u3002<\/p>\n
\u6211\u4eec\u77e5\u9053\u6570\u5b57\u5728\u8ba1\u7b97\u673a\u4e2d\u662f\u4ee5\u4e8c\u8fdb\u5236\u7684\u5f62\u5f0f\u5b58\u50a8\u7684\u3002\u6d6e\u70b9\u6570\u5927\u81f4\u662f\u4ee5\\((-1)^\\text{sign}\\times\\text{fraction}\\times 2^\\text{exponent}\\)\u7684\u5f62\u5f0f\u8868\u793a\u7684\uff0c\u5982\u56fe\uff1a\uff08\u56fe\u7247\u5f15\u7528\u81ea\u7ef4\u57fa\u767e\u79d1\uff09<\/p>\n
\"618px-IEEE_754_Double_Floating_Point_Format.svg\"<\/a><\/p>\n
\u7528\u6d6e\u70b9\u6570\u8868\u793a2\u7684n\u6b21\u65b9\u7684\u65f6\u5019\uff0c\u5c3e\u6570\u90e8\u5206\u53d61\u5373\u53ef\uff0c\u5373\\(1\\times 2^n\\)\uff0c\u6240\u4ee5\u4e0d\u4f1a\u635f\u5931\u7cbe\u5ea6\u3002<\/p>\n
\u6253\u4e00\u4e2a\u6bd4\u65b9\uff0c\u5728\u5341\u8fdb\u5236\u4e2d\uff0c\u6211\u4eec\u628a34500000000\u5199\u6210\u79d1\u5b66\u8ba1\u6570\u6cd5\uff0c\u4fdd\u7559\u4e09\u4f4d\u5c0f\u6570\uff0c\u53733.45e10\uff0c\u4e0d\u4f1a\u635f\u5931\u7cbe\u5ea6\uff1b\u4f46\u662f\u5982\u679c\u6211\u4eec\u628a34512345678\u5199\u6210\u79d1\u5b66\u8ba1\u6570\u6cd5\uff0c\u4fdd\u7559\u4e09\u4f4d\u5c0f\u6570\uff0c\u4e5f\u662f3.45e10\uff0c\u8fd9\u6837\u5c31\u4f1a\u635f\u5931\u7cbe\u5ea6\u4e86\u3002\u6b63\u598234500000000\u5728\u5341\u8fdb\u5236\u4e2d\u662f\u4e00\u4e2a\u5f88\u201c\u6574\u201d\u7684\u6570\uff0c2\u7684n\u6b21\u65b9\u5728\u4e8c\u8fdb\u5236\u4e2d\u4e5f\u662f\u5f88\u201c\u6574\u201d\u7684\u6570\u3002<\/p>\n
\u987a\u4fbf\u8bf4\u4e00\u4e0b\uff0c\u4e8c\u8fdb\u5236\u4e2d\u53ea\u6709\u8868\u793a\u6210\u5206\u6570\u540e\u5206\u6bcd\u662f2\u7684n\u6b21\u65b9\u7684\u5c0f\u6570\u624d\u80fd\u591f\u5199\u6210\u6709\u9650\u4f4d\u5c0f\u6570\uff0c\u4f8b\u5982\\(0.5625=\\frac{9}{16}=(0.1001)_2\\)\u3002\u7136\u800c\u5728\u5341\u8fdb\u5236\u4e2d\u50cf0.1\u30010.2\u8fd9\u6837\u7684\u6709\u9650\u4f4d\u5c0f\u6570\u8f6c\u6362\u6210\u4e8c\u8fdb\u5236\u6570\u90fd\u662f\u65e0\u9650\u5faa\u73af\u5c0f\u6570\uff0c\u4f8b\u5982\\(0.1=(0.0001100110011…)_2\\)\uff0c\u4ece\u800c\u8fd9\u6837\u7684\u6570\u5728\u6d6e\u70b9\u6570\u4e2d\u4e0d\u80fd\u5b8c\u5168\u7cbe\u786e\u7684\u8868\u793a\u3002<\/p>\n
\u5f53\u7528cout\u8f93\u51fa\u65f6\uff0c\u56e0\u4e3a\u5df2\u7ecf\u6307\u5b9a\u4e86precision(0)\u548cfixed\uff0c\u7a0b\u5e8f\u5728\u6253\u5370\u6d6e\u70b9\u6570\u7684\u65f6\u5019\u4f1a\u4ee5\u7cbe\u786e\u5230\u4e2a\u4f4d\u7684\u5341\u8fdb\u5236\u6570\u6253\u5370\u51fa\u6765\uff0c\u81ea\u7136\u4e5f\u5c31\u662f\u7cbe\u786e\u7684\u4e86\u3002\u9ad8\u7cbe\u5ea6\u8ba1\u7b97\u662f\u5728\u201c\u4e8c\u8fdb\u5236\u8f6c\u6362\u4e3a\u5341\u8fdb\u5236\u201d\u7684\u8fc7\u7a0b\u4e2d\u53d1\u751f\u7684\u3002<\/p>\n
\u6211\u8bd5\u7740\u628a\u7a0b\u5e8f\u6539\u6210\u8c03\u7528long double\u7c7b\u578b\u7684pow\u51fd\u6570\uff0c\u8fd9\u6837\u6700\u591a\u53ef\u4ee5\u8ba1\u7b97\u52302\u768416383\u6b21\u65b9\uff0c\u7ed3\u679c\u4e5f\u662f\u5b8c\u5168\u7cbe\u786e\u7684\u3002<\/p>\n
\"16383\"<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
\u8fd9\u4e2a\u60f3\u6cd5\u6e90\u4e8e\u4e00\u9053\u7a0b\u5e8f\u8bbe\u8ba1\u8bfe\u7684\u4e0a\u673a\u9898\uff1a\u4efb\u610f\u7ed9\u5b9a\u4e00\u4e2a\u6b63\u6574\u6570N(N<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[],"class_list":["post-198","post","type-post","status-publish","format-standard","hentry","category-c-language"],"_links":{"self":[{"href":"https:\/\/sqrt-1.me\/index.php?rest_route=\/wp\/v2\/posts\/198","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sqrt-1.me\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sqrt-1.me\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sqrt-1.me\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sqrt-1.me\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=198"}],"version-history":[{"count":11,"href":"https:\/\/sqrt-1.me\/index.php?rest_route=\/wp\/v2\/posts\/198\/revisions"}],"predecessor-version":[{"id":337,"href":"https:\/\/sqrt-1.me\/index.php?rest_route=\/wp\/v2\/posts\/198\/revisions\/337"}],"wp:attachment":[{"href":"https:\/\/sqrt-1.me\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=198"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sqrt-1.me\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=198"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sqrt-1.me\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=198"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}