{"id":274589,"date":"2021-01-12T14:01:36","date_gmt":"2021-01-12T06:01:36","guid":{"rendered":"http:\/\/4563.org\/?p=274589"},"modified":"2021-01-12T14:01:36","modified_gmt":"2021-01-12T06:01:36","slug":"leetcode-%e4%b8%ad%e4%bd%bf%e7%94%a8-stringbuilder-%e8%bf%9e%e6%8e%a5%e5%ad%97%e7%ac%a6%e4%b8%b2%e4%b8%ba%e4%bb%80%e4%b9%88%e4%bc%9a%e6%af%94%e7%94%a8%e5%8f%b7%e8%bf%9e%e6%8e%a5%e5%bf%ab%ef%bc%9f","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=274589","title":{"rendered":"LeetCode \u4e2d\u4f7f\u7528 StringBuilder \u8fde\u63a5\u5b57\u7b26\u4e32\u4e3a\u4ec0\u4e48\u4f1a\u6bd4\u7528+\u53f7\u8fde\u63a5\u5feb\uff1f"},"content":{"rendered":"<div>\n<div>\n<div>\n<h1>                  LeetCode \u4e2d\u4f7f\u7528 StringBuilder \u8fde\u63a5\u5b57\u7b26\u4e32\u4e3a\u4ec0\u4e48\u4f1a\u6bd4\u7528+\u53f7\u8fde\u63a5\u5feb\uff1f               <\/h1>\n<p> <\/p>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : kuretru <\/span>  <span><i><\/i> 0<\/span> <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<div isfirst=\"1\"> <\/p>\n<p>\u4eca\u65e5 LeetCode \u7684\u6bcf\u65e5\u4e00\u9898\uff0c\u4ee3\u7801\u5f88\u7b80\u5355\uff0c\u5b98\u65b9\u7684\u9898\u89e3\u5982\u4e0b\uff1a<\/p>\n<pre><code>class Solution {     public List&lt;String&gt; summaryRanges(int[] nums) {         List&lt;String&gt; ret = new ArrayList&lt;String&gt;();         int i = 0;         int n = nums.length;         while (i &lt; n) {             int low = i;             i++;             while (i &lt; n &amp;&amp; nums[i] == nums[i - 1] + 1) {                 i++;             }             int high = i - 1;             StringBuffer temp = new StringBuffer(Integer.toString(nums[low]));             if (low &lt; high) {                 temp.append(\"-&gt;\");                 temp.append(Integer.toString(nums[high]));             }             ret.add(temp.toString());         }         return ret;     } } <\/code><\/pre>\n<p>\u53ef\u4ee5\u770b\u5230\u5b98\u65b9\u4f7f\u7528 StringBuffer \u6765\u8fde\u63a5\u5b57\u7b26\u4e32\uff0c\u5728\u4e0d\u9700\u8981\u8003\u8651\u7ebf\u7a0b\u5b89\u5168\u7684\u73af\u5883\uff0c\u6beb\u65e0\u7591\u95ee\u53ef\u4ee5\u4f7f\u7528 StringBuilder \u6765\u4ee3\u66ff\uff0c\u4f46\u662f\u95ee\u9898\u5728\u4e8e\uff0c\u4e3a\u4ec0\u4e48\u4f7f\u7528+\u53f7\u6765\u8fde\u63a5\u7684\u6548\u679c\u4f1a\u6bd4 StringBuilder \u53ca StringBuffer \u5dee\uff1f<\/p>\n<pre><code>String temp = Integer.toString(nums[low]); if (low &lt; high) { temp += \"-&gt;\" + Integer.toString(nums[high]); } ret.add(temp); <\/code><\/pre>\n<p>\u4e24\u8005\u7684\u5dee\u522b\u4e3a\uff1a<br \/> <code>StringBuilder\/StringBuffer\uff1a<\/code>\u6267\u884c\u7528\u65f6\uff1a0 ms, \u5728\u6240\u6709 Java \u63d0\u4ea4\u4e2d\u51fb\u8d25\u4e86 100.00%\u7684\u7528\u6237<br \/> <code>\uff0b\u53f7\u8fde\u63a5\uff1a<\/code>\u6267\u884c\u7528\u65f6\uff1a8 ms, \u5728\u6240\u6709 Java \u63d0\u4ea4\u4e2d\u51fb\u8d25\u4e86 70.02%\u7684\u7528\u6237<br \/> \u540c\u6837\u7684\u4ee3\u7801\u5728\u672c\u5730\u5404\u5faa\u73af 1000 \u4e07\u6b21\u7684\u7ed3\u679c\u4e3a<br \/> JDK 1.8(\u4e0e LeetCode \u76f8\u540c)\uff1a7708ms vs 7287ms<br \/> JDK 11\uff1a7320ms vs 4511ms<\/p>\n<\/p><\/div>\n<div> <b>\u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (<span>9<\/span>)        <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<ul>\n<li data-pid=\"4910304\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : snw <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u6211\u8bb0\u5f97\u5927\u81f4\u4e0a\u662f\u56e0\u4e3a\u7528 + \u65f6\uff0c\u5185\u90e8\u4f1a\u521b\u5efa\u4e00\u4e2a\u65b0\u7684 string\uff0c\u7136\u540e\u628a\u8fde\u63a5\u7684\u503c\u8d4b\u7ed9\u8fd9\u4e2a\u65b0\u7684 string \u3002<br \/>\u7528 StringBuilder \u7684\u8bdd\u662f\u76f4\u63a5\u628a\u589e\u52a0\u7684\u5b57\u7b26 append \u5230\u539f\u5b57\u7b26\u4e32\u540e\u9762\uff0c\u7701\u53bb\u4e86\u521b\u5efa\u65b0 string \u3001\u5220\u9664\u65e7 string \u7684\u6d88\u8017\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910305\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : kuretru <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @snw #1 <br \/>\u4f60\u8bf4\u7684\u662f\u5faa\u73af\u5185\u7684\u60c5\u51b5\u628a<br \/>&#8220;`java<br \/>String text = &#8220;&#8221;;<br \/>for(){<br \/> test += something;<br \/>}<br \/>&#8220;`<br \/>\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u4f7f\u7528 StringBuilder \u548c StringBuffer \u65e0\u7591                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910306\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : vincentxue <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u8fd9\u4e2a\u548c\u5faa\u73af\u6ca1\u5173\u7cfb\uff0c\u5faa\u73af\u53ea\u662f\u8fdb\u4e00\u6b65\u653e\u5927\u4e86\u6027\u80fd\u95ee\u9898\uff0c\u5b57\u7b26\u4e32\u53ea\u8981\u662f\u62fc\u63a5\u53d8\u91cf\uff0c\u4e0d\u7ba1\u653e\u5728\u54ea\u91cc\uff0c\u7f16\u8bd1\u5668\u90fd\u4f1a\u7ed9\u4f60\u6362\u6210 StringBuilder \u7684\u3002\u6700\u76f4\u63a5\u7684\u529e\u6cd5\u5c31\u662f\u628a\u4f60\u4e24\u4efd\u4ee3\u7801\u8f6c\u6210\u5b57\u8282\u7801\u4e00\u5bf9\u6bd4\u4f60\u5c31\u80fd\u770b\u660e\u767d\u91cc\u9762\u7684\u539f\u56e0\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910307\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : Merlini <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u6b63\u597d\u6700\u8fd1\u5728\u5165\u95e8 java<\/p>\n<p>&gt; \u6709\u4e9b\u65f6\u5019 \uff0c \u9700\u8981\u7531\u8f83\u77ed\u7684\u5b57\u7b26\u4e32\u6784\u5efa\u5b57\u7b26\u4e32 \uff0c \u4f8b\u5982 \uff0c \u6309\u952e\u6216\u6765\u81ea\u6587\u4ef6\u4e2d\u7684\u5355\u8bcd\u3002 \u91c7\u7528\u5b57\u7b26\u4e32\u8fde\u63a5\u7684\u65b9\u5f0f\u8fbe\u5230\u6b64\u76ee\u7684\u6548\u7387\u6bd4\u8f83\u4f4e\u3002 \u6bcf\u6b21\u8fde\u63a5\u5b57\u7b26\u4e32 \uff0c\u90fd\u4f1a\u6784\u5efa\u4e00\u4e2a\u65b0\u7684 String \u5bf9\u8c61 \uff0c\u65e2\u8017\u65f6 \uff0c \u53c8\u6d6a\u8d39\u7a7a\u95f4\u3002 \u4f7f\u7528 StringBuilder \u7c7b\u5c31\u53ef\u4ee5\u907f\u514d\u8fd9\u4e2a\u95ee\u9898\u7684\u53d1\u751f\u3002 <br \/>\u53d6\u81ea java \u6838\u5fc3\u5377 1                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910308\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : micean <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u8fd9\u662f java \u7684\u57fa\u7840\u95ee\u9898\u554a\u2026\u2026\u52a0\u53f7\u5728\u4e0d\u53ef\u4f18\u5316\u7684\u60c5\u51b5\u4e0b\u6bcf\u4f7f\u7528\u4e00\u6b21\u76f8\u5f53\u4e8e\u62f7\u8d1d\u4e86\u4e00\u6b21\u65e7\u4e32 byte[]\u548c\u65b0\u589e\u4e32 byte[]\uff0c\u6027\u80fd\u5f53\u7136\u5c31\u4f4e\u4e86                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910309\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : AllenHua <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u5982\u679c\u53ea\u662f\u7b80\u5355\u7684\u5b57\u7b26\u4e32\u62fc\u63a5 \u4f7f\u7528 concat \u6bd4 \u4f7f\u7528 + \u6548\u7387\u66f4\u9ad8<\/p>\n<p>\u4f46\u662f concat \u53ea\u80fd concat String \u7c7b\u578b\u7684\u6570\u636e<\/p>\n<p>+ \u53ef\u4ee5 \u62fc\u63a5\u5176\u4ed6\u57fa\u7840\u7c7b\u578b\u7684\u6570\u636e<\/p>\n<p>\u8001\u751f\u5e38\u8c08 \u5982\u679c\u5927\u91cf\u64cd\u4f5c String \u52a1\u5fc5\u4f7f\u7528\u5c01\u88c5\u7c7b StringBuffer \u6216 StringBuilder \u6216 StringJoiner                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910310\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : hoyixi <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u8fd9\u662f N \u5e74\u524d\u9762\u8bd5\u5b98\u7231\u95ee\u7684\u95ee\u9898\uff0c\u5df2\u7ecf\u88ab\u95ee\u70c2\u4e86                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910311\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : Jooooooooo <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             String \u7684 + \u6bcf\u6b21\u90fd new \u5bf9\u8c61<\/p>\n<p>\u975e\u5e38\u5927\u7684\u5faa\u73af\u8bb0\u5f97\u7528 StringBuilder                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4910312\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : 340244120w <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             \u4e0a\u5927\u90e8\u5206\u90fd\u770b\u7684 java \u6838\u5fc3\u601d\u60f3\u5427\u3002\u5176\u5b9e\u73b0\u5728 8 \u4e4b\u540e\uff0c\u5faa\u73af\u91cc\u76f4\u63a5\u62fc\u5b57\u7b26\u4e32\uff0c\u76f8\u5f53\u4e8e\u6bcf\u6b21\u5faa\u73af\u90fd\u521b\u5efa\u4e86\u4e00\u4e2a stringbuilder\uff0c\u76f8\u5bf9\u4e8e\u5faa\u73af\u5916\u9762\u53ea\u521b\u5efa\u4e00\u4e2a\uff0c\u81ea\u7136\u5c31\u6162\u4e86                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li>\n","protected":false},"excerpt":{"rendered":"<p>LeetCode \u4e2d\u4f7f\u7528 Stri&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\/274589"}],"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=274589"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/274589\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=274589"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=274589"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=274589"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}