{"id":216820,"date":"2020-11-26T13:27:16","date_gmt":"2020-11-26T05:27:16","guid":{"rendered":"http:\/\/4563.org\/?p=216820"},"modified":"2020-11-26T13:27:16","modified_gmt":"2020-11-26T05:27:16","slug":"%e8%af%b7%e6%95%99%e4%b8%80%e4%b8%8b%e8%bf%99%e6%ae%b5%e4%bb%a3%e7%a0%81%e7%9a%84%e6%97%b6%e9%97%b4%e5%a4%8d%e6%9d%82%e5%ba%a6","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=216820","title":{"rendered":"\u8bf7\u6559\u4e00\u4e0b\u8fd9\u6bb5\u4ee3\u7801\u7684\u65f6\u95f4\u590d\u6742\u5ea6"},"content":{"rendered":"<div>\n<div>\n<div>\n<h1>                  \u8bf7\u6559\u4e00\u4e0b\u8fd9\u6bb5\u4ee3\u7801\u7684\u65f6\u95f4\u590d\u6742\u5ea6               <\/h1>\n<p> <\/p>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : Helsing <\/span>  <span><i><\/i> 2<\/span> <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<div isfirst=\"1\"> <\/p>\n<pre><code>\/\/ \u5168\u5c40\u53d8\u91cf\uff0c\u5927\u5c0f\u4e3a 10 \u7684\u6570\u7ec4 array\uff0c\u957f\u5ea6 len\uff0c\u4e0b\u6807 i \u3002 int array[] = new int[10];  int len = 10; int i = 0;  \/\/ \u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4e00\u4e2a\u5143\u7d20 void add(int element) {    if (i &gt;= len) { \/\/ \u6570\u7ec4\u7a7a\u95f4\u4e0d\u591f\u4e86      \/\/ \u91cd\u65b0\u7533\u8bf7\u4e00\u4e2a 2 \u500d\u5927\u5c0f\u7684\u6570\u7ec4\u7a7a\u95f4      int new_array[] = new int[len * 2];      \/\/ \u628a\u539f\u6765 array \u6570\u7ec4\u4e2d\u7684\u6570\u636e\u4f9d\u6b21 copy \u5230 new_array      for (int j = 0; j &lt; len; ++j) {        new_array[j] = array[j];      }      \/\/ new_array \u590d\u5236\u7ed9 array\uff0carray \u73b0\u5728\u5927\u5c0f\u5c31\u662f 2 \u500d len \u4e86      array = new_array;      len = 2 * len;    }    \/\/ \u5c06 element \u653e\u5230\u4e0b\u6807\u4e3a i \u7684\u4f4d\u7f6e\uff0c\u4e0b\u6807 i \u52a0\u4e00    array[i] = element;    ++i; } <\/code><\/pre>\n<p>\u8fd9\u662f\u6211\u5728\u4e00\u4e2a\u8bfe\u7a0b\u91cc\u770b\u5230\u7684\u4f8b\u5b50\uff0c\u5047\u5982\u8bf4\u8c03\u7528 n \u6b21 add \u65b9\u6cd5\uff0c<strong>\u6700\u597d\u65f6\u95f4\u590d\u6742\u5ea6<\/strong>\u3001<strong>\u6700\u574f\u65f6\u95f4\u590d\u6742\u5ea6<\/strong>\u548c<strong>\u5e73\u5747\u65f6\u95f4\u590d\u6742\u5ea6<\/strong>\u5206\u522b\u662f\u591a\u5c11\uff1f<\/p>\n<p>\u4e0b\u9762\u8fd9\u4e2a\u662f\u8bfe\u7a0b\u8bc4\u8bba\u4e2d\u7684\u4e00\u4e2a\u7b54\u6848\uff0c\u8bb2\u5e08\u4e5f\u8bf4\u662f\u5bf9\u7684\uff1a<\/p>\n<ol>\n<li>\n<p>\u6700\u597d\u60c5\u51b5\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a <strong>O(1)<\/strong><\/p>\n<\/li>\n<li>\n<p>\u6700\u574f\u60c5\u51b5\u5206\u6790\uff1a<\/p>\n<p>\u6700\u574f\u60c5\u51b5\u4ee3\u7801\u6267\u884c\u7684\u6b21\u6570\u8ddf\u6bcf\u6b21\u6570\u7ec4\u7684\u957f\u5ea6\u6709\u5173<\/p>\n<p>\u7b2c 1 \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>n<\/em> ,<\/p>\n<p>\u7b2c 2 \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>2n<\/em> ,<\/p>\n<p>\u7b2c 3 \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>2^2 * n<\/em><\/p>\n<p>\u7b2c k \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>2^(k-1) * n<\/em><\/p>\n<p>\u6700\u574f\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a <strong>O(n)<\/strong>\u3002<\/p>\n<\/li>\n<li>\n<p>\u5e73\u5747\u60c5\u51b5\u5206\u6790 \u5f53\u6bcf\u6b21\u9047\u5230\u6700\u574f\u60c5\u51b5\u65f6\u6570\u7ec4\u4f1a\u8fdb\u884c 2 \u500d\u6269\u5bb9\uff0c\u539f\u6570\u7ec4\u88ab\u5bfc\u5165\u65b0\u6570\u7ec4\uff0c\u867d\u7136\u6570\u7ec4\u7684\u957f\u5ea6\u53d8\u5927\u4e86\uff0c\u4f46\u662f\u63d2\u5165\u64cd\u4f5c\u843d\u5728\u7684\u533a\u95f4\u7684\u957f\u5ea6\u662f\u4e00\u6837\u7684\uff0c\u5206\u522b\u662f <em>0~len-1<\/em>, <em>len~(2len-1)<\/em>, &#8230;.\uff1b<\/p>\n<p>\u63d2\u5165\u7684\u60c5\u51b5\u4ecd\u662f <em>len+1<\/em> \u79cd\uff1a<em>0~len-1<\/em> \u548c\u63d2\u6ee1\u4e4b\u540e\u7684 <em>O(len)<\/em>\uff1b<\/p>\n<p>\u6240\u4ee5\u6bcf\u6b21\u63d2\u5165\u7684\u6982\u7387\u662f\uff1a<em>p= 1\/len+1<\/em>\uff0c<\/p>\n<p>\u6700\u540e\u6c42\u51fa\u52a0\u6743\u5e73\u5747\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a <em>1*p + 2*p+ \u25aa\u25aa\u25aa + len * p + len * p = O(1)<\/em> ;<\/p>\n<\/li>\n<li>\n<p>\u5747\u644a\u65f6\u95f4\u590d\u6742\u5ea6 <strong>O(1)<\/strong><\/p>\n<\/li>\n<li>\n<p>\u800c\u5747\u644a\u590d\u6742\u5ea6\u7531\u4e8e\u6bcf\u6b21 <em>O(len)<\/em> \u7684\u51fa\u73b0\u90fd\u8ddf\u7740 <em>len<\/em> \u6b21 <em>O(1)<\/em>\uff0c\u662f\u524d\u540e\u8fde\u8d2f\u7684\uff0c\u56e0\u800c\u5c06 <em>O(len)<\/em> \u5e73\u644a\u5230\u524d <em>len<\/em> \u6b21\u4e0a\uff0c\u5f97\u51fa\u5e73\u644a\u590d\u6742\u5ea6\u662f <em>O(1)<\/em><\/p>\n<\/li>\n<\/ol>\n<p>\u4f46\u662f\u6309\u6211\u7684\u7406\u89e3\uff1a<\/p>\n<ul>\n<li>\n<p>\u6700\u574f\u60c5\u51b5\u5206\u6790\uff1a<\/p>\n<p>\u6700\u574f\u60c5\u51b5\u4ee3\u7801\u6267\u884c\u7684\u6b21\u6570\u8ddf\u6bcf\u6b21\u6570\u7ec4\u7684\u957f\u5ea6\u6709\u5173<\/p>\n<p>\u7b2c 1 \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>2^0 * 10<\/em>,<\/p>\n<p>\u7b2c 2 \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>2^1 * 10<\/em> ,<\/p>\n<p>\u7b2c 3 \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>2^2 * 10<\/em><\/p>\n<p>\u7b2c n \u6b21\u8c03\u7528 add \u7684\u6267\u884c\u7684\u6b21\u6570\u4e3a <em>2^(n-1) * 10 = 2^n * 5<\/em><\/p>\n<p>\u5e38\u7cfb\u6570\u53ef\u4ee5\u7701\u7565\uff0c\u6240\u4ee5\u8c03\u7528 n \u6b21 add \u65b9\u6cd5\u7684\u6700\u5dee\u65f6\u95f4\u590d\u6742\u5ea6\u5e94\u8be5\u65f6 <em><strong>2^n<\/strong><\/em>\u3002<\/p>\n<\/li>\n<\/ul>\n<p>\u6211\u770b\u8bfe\u7a0b\u8bc4\u8bba\u91cc\u9762\u90fd\u628a\u6570\u7ec4\u7684\u957f\u5ea6\u5047\u8bbe\u4e3a n\uff0c\u4f46\u662f\u6570\u7ec4\u7684\u521d\u59cb\u957f\u5ea6\u660e\u660e\u662f 10\uff0c\u8fd9\u6837\u5047\u8bbe\u7684\u8bdd\u8ddf\u4e0a\u9762\u7684\u4ee3\u7801\u6839\u672c\u5c31\u4e0d\u662f\u4e00\u4e2a\u610f\u601d\u4e86\u3002\u6211\u89c9\u5f97 n \u5e94\u8be5\u662f\u8c03\u7528 add \u7684\u6b21\u6570\u624d\u5bf9\u3002<\/p>\n<p>\u5927\u5bb6\u600e\u4e48\u770b\uff1f<\/p>\n<\/p><\/div>\n<div> <b>\u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (<span>0<\/span>)        <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<ul>\n<li>\n","protected":false},"excerpt":{"rendered":"<p>\u8bf7\u6559\u4e00\u4e0b\u8fd9\u6bb5\u4ee3\u7801\u7684\u65f6\u95f4\u590d\u6742\u5ea6 \u8cc7\u6df1&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/216820"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=216820"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/216820\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=216820"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=216820"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=216820"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}