{"id":860,"date":"2025-08-07T18:43:41","date_gmt":"2025-08-07T10:43:41","guid":{"rendered":"https:\/\/www.guanhaobo.cn\/?p=860"},"modified":"2025-08-07T18:43:41","modified_gmt":"2025-08-07T10:43:41","slug":"leetcode-128-%e6%9c%80%e9%95%bf%e8%bf%9e%e7%bb%ad%e5%ba%8f%e5%88%97","status":"publish","type":"post","link":"https:\/\/www.guanhaobo.cn\/?p=860","title":{"rendered":"LeetCode 128 &#8211; \u6700\u957f\u8fde\u7eed\u5e8f\u5217"},"content":{"rendered":"<h1>\u9898\u76ee\u63cf\u8ff0<\/h1>\n<p>\u7ed9\u5b9a\u4e00\u4e2a\u672a\u6392\u5e8f\u7684\u6574\u6570\u6570\u7ec4 nums \uff0c\u627e\u51fa\u6570\u5b57\u8fde\u7eed\u7684\u6700\u957f\u5e8f\u5217\uff08\u4e0d\u8981\u6c42\u5e8f\u5217\u5143\u7d20\u5728\u539f\u6570\u7ec4\u4e2d\u8fde\u7eed\uff09\u7684\u957f\u5ea6\u3002<\/p>\n<p>\u8bf7\u4f60\u8bbe\u8ba1\u5e76\u5b9e\u73b0\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a O(n) \u7684\u7b97\u6cd5\u89e3\u51b3\u6b64\u95ee\u9898\u3002<\/p>\n<pre><code class=\"line-numbers\">\u793a\u4f8b 1\uff1a\n\u8f93\u5165\uff1anums = [100,4,200,1,3,2]\n\u8f93\u51fa\uff1a4\n\u89e3\u91ca\uff1a\u6700\u957f\u6570\u5b57\u8fde\u7eed\u5e8f\u5217\u662f [1, 2, 3, 4]\u3002\u5b83\u7684\u957f\u5ea6\u4e3a 4\u3002\n\n\u793a\u4f8b 2\uff1a\n\u8f93\u5165\uff1anums = [0,3,7,2,5,8,4,6,0,1]\n\u8f93\u51fa\uff1a9\n\n\u793a\u4f8b 3\uff1a\n\u8f93\u5165\uff1anums = [1,0,1,2]\n\u8f93\u51fa\uff1a3\n<\/code><\/pre>\n<h1>\u9898\u76ee\u5206\u6790<\/h1>\n<h2>\u66b4\u529b\u6c42\u89e3<\/h2>\n<p>\u5c06\u6240\u6709\u5143\u7d20\u653e\u5165<code>HashSet<\/code>\uff0c\u4fbf\u4e8e\u540e\u7eed\u68c0\u67e5\u67d0\u4e2a\u6570\u5b57\u662f\u5426\u5b58\u5728\u3002<br \/>\n\u679a\u4e3e\u6bcf\u4e00\u4e2a\u5143\u7d20\uff1a\u5047\u8bbe\u5f53\u524d\u6570\u5b57n\u662f\u5e8f\u5217\u7684\u8d77\u70b9\uff0c\u5199\u4e00\u4e2a\u5faa\u73af\uff0c\u68c0\u67e5n+1\u662f\u5426\u5b58\u5728\uff0c\u4ee5\u6b64\u7c7b\u63a8\uff0c\u76f4\u5230+1\u4e0d\u5b58\u5728\uff0c\u5c31\u5f97\u5230\u4e86\u4ee5\u6570\u5b57n\u4e3a\u8d77\u70b9\u7684\u6700\u957f\u5e8f\u5217\u7684\u957f\u5ea6\u3002\u6240\u6709\u5143\u7d20\u679a\u4e3e\u5b8c\uff0c\u5c31\u53ef\u4ee5\u5f97\u5230\u6700\u5927\u957f\u5ea6\u3002<br \/>\n\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a <code>O(n^2)<\/code><\/p>\n<h2>\u6761\u4ef6\u4f18\u5316<\/h2>\n<p>\u5bf9\u4e8e\u6570\u5b57 n\uff0c\u5982\u679c n-1 \u5b58\u5728\u4e8e\u6570\u7ec4\u4e2d\uff0c\u90a3\u4e48 n \u4e00\u5b9a\u4e0d\u662f\u6700\u957f\u8fde\u7eed\u5e8f\u5217\u7684\u8d77\u70b9\u3002\u8fd9\u6837\u5c31\u53ef\u4ee5\u5bf9\u65f6\u95f4\u590d\u6742\u5ea6\u505a\u4f18\u5316\uff0c\u5916\u5c42\u5bf9\u8d77\u70b9\u7684\u679a\u4e3e\u4f9d\u7136\u4f1a\u6267\u884c n \u6b21\uff0c\u4f46\u5185\u5c42\u7684 +1 \u5faa\u73af\u5224\u65ad\u5168\u5c40\u53ea\u4f1a\u6267\u884c n \u6b21\u3002<br \/>\n\u603b\u7684\u6267\u884c\u6b21\u6570\u662f 2n\uff0c\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a <code>O(n)<\/code><\/p>\n<h1>Java<\/h1>\n<pre><code class=\"language-java line-numbers\">public int longestConsecutive(int[] nums) {\n    HashSet&lt;Integer&gt; set = new HashSet&lt;&gt;();\n    if (nums.length == 0) {\n        return 0;\n    }\n    for (int num : nums) {\n        set.add(num);\n    }\n\n    int ans = 0;\n\n    for (int num : set) {\n        if (set.contains(num - 1)) {\n            continue;\n        }\n        int current = num;\n        int len = 0;\n        while (set.contains(current)) {\n            len++;\n            current++;\n        }\n        ans = Math.max(ans, len);\n    }\n\n    return ans;\n}\n<\/code><\/pre>\n<h1>Kotlin<\/h1>\n<pre><code class=\"language-kotlin line-numbers\">fun longestConsecutive(nums: IntArray): Int {\n    val set = HashSet&lt;Int&gt;()\n    set.addAll(nums.toList())\n    var ans = 0\n    for (n in nums) {\n        if (set.contains(n - 1)) {\n            continue\n        }\n        var t = n\n        var len = 0\n        while (set.contains(t)) {\n            t++\n            len++\n        }\n        ans = max(ans, len)\n    }\n    return ans\n}\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u9898\u76ee\u63cf\u8ff0 \u7ed9\u5b9a\u4e00\u4e2a\u672a\u6392\u5e8f\u7684\u6574\u6570\u6570\u7ec4 nums \uff0c\u627e\u51fa\u6570\u5b57\u8fde\u7eed\u7684\u6700\u957f\u5e8f\u5217\uff08\u4e0d\u8981\u6c42\u5e8f\u5217\u5143\u7d20\u5728\u539f\u6570\u7ec4\u4e2d\u8fde\u7eed\uff09\u7684\u957f\u5ea6\u3002 [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[20,74,73],"class_list":["post-860","post","type-post","status-publish","format-standard","hentry","category-algo","tag-leetcode","tag-74","tag-73"],"_links":{"self":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/860","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=860"}],"version-history":[{"count":1,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/860\/revisions"}],"predecessor-version":[{"id":861,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/860\/revisions\/861"}],"wp:attachment":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=860"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=860"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=860"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}