{"id":53052,"date":"2024-12-03T08:33:01","date_gmt":"2024-12-03T00:33:01","guid":{"rendered":"https:\/\/fwq.ai\/blog\/53052\/"},"modified":"2024-12-03T08:33:01","modified_gmt":"2024-12-03T00:33:01","slug":"javascript-%e4%b8%ad%e7%9a%84-set%ef%bc%88%e5%88%9d%e5%ad%a6%e8%80%85%e6%95%99%e7%a8%8b%ef%bc%89","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/53052\/","title":{"rendered":"JavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09"},"content":{"rendered":"<p><b><\/b>     <\/p>\n<h1>JavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09<\/h1>\n<p><span style=\"cursor: pointer\"><i><\/i>\u6536\u85cf<\/span>    <\/p>\n<p>\u4eca\u5929\u7c73\u4e91\u7ed9\u5927\u5bb6\u5e26\u6765\u4e86<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\">\u300aJavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09\u300b<\/span>\uff0c\u5176\u4e2d\u6d89\u53ca\u5230\u7684\u77e5\u8bc6\u70b9\u5305\u62ec<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\"><\/span>\u7b49\u7b49\uff0c\u65e0\u8bba\u4f60\u662f\u5c0f\u767d\u8fd8\u662f\u8001\u624b\uff0c\u90fd\u9002\u5408\u770b\u4e00\u770b\u54e6~\u6709\u597d\u7684\u5efa\u8bae\u4e5f\u6b22\u8fce\u5927\u5bb6\u5728\u8bc4\u8bba\u7559\u8a00\uff0c\u82e5\u662f\u770b\u5b8c\u6709\u6240\u6536\u83b7\uff0c\u4e5f\u5e0c\u671b\u5927\u5bb6\u80fd\u591a\u591a\u70b9\u8d5e\u652f\u6301\u5440\uff01\u4e00\u8d77\u52a0\u6cb9\u5b66\u4e60~<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20241126\/1732588029674531fdc04ff.jpg\" class=\"aligncenter\" title=\"JavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09\u63d2\u56fe\" alt=\"JavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09\u63d2\u56fe\" \/><\/p>\n<p>\u4f60\u597d\uff0c<\/p>\n<p>\u60a8\u662f\u5426\u6b63\u5728\u5bfb\u627e\u4e00\u79cd\u5b58\u50a8\u552f\u4e00\u503c\u3001\u5141\u8bb8\u63d2\u5165\u503c\u3001\u67e5\u627e\u503c\u603b\u6570\u548c\u5220\u9664\u503c\u7684\u6570\u636e\u7ed3\u6784\uff1f\u5957\u88c5\u662f\u6700\u4f73\u9009\u62e9\u3002\u8bb8\u591a\u7f16\u7a0b\u8bed\u8a00\u90fd\u5305\u542b\u5185\u7f6e\u7684 set \u6570\u636e\u7ed3\u6784\uff0cjavascript \u4e5f\u4e0d\u4f8b\u5916\u3002\u8ba9\u6211\u4eec\u66f4\u6df1\u5165\u5730\u4e86\u89e3\u96c6\u5408\u7684\u5de5\u4f5c\u539f\u7406\u3002 <\/p>\n<p><strong>\u8bbe\u7f6e\u662f\u4ec0\u4e48\uff1f<\/strong> \u200b\u200b<br \/> set \u662f\u4e00\u79cd\u6570\u636e\u7ed3\u6784\uff0c\u53ef\u8ba9\u60a8\u5b58\u50a8\u4efb\u4f55\u7c7b\u578b\u7684\u552f\u4e00\u503c\uff0c\u65e0\u8bba\u662f\u539f\u59cb\u503c\u8fd8\u662f\u5bf9\u8c61\u5f15\u7528\u3002\u8be5\u96c6\u5408\u5141\u8bb8\u6267\u884c o(1) \u65f6\u95f4\u590d\u6742\u5ea6\u7684\u63d2\u5165\u3001\u5220\u9664\u3001\u66f4\u65b0\u548c\u5927\u5c0f\u64cd\u4f5c\u3002\u8fd9\u4f7f\u5f97\u8bbe\u7f6e\u66f4\u5feb\u3001\u66f4\u9ad8\u6548\u3002 <\/p>\n<p>\u5957\u88c5\u65e8\u5728\u63d0\u4f9b\u5feb\u901f\u8bbf\u95ee\u65f6\u95f4\u3002\u5b83\u4eec\u7684\u5b9e\u73b0\u65b9\u5f0f\u901a\u5e38\u4f7f\u67e5\u627e\u9879\u76ee\u6bd4\u7b80\u5355\u5730\u9010\u9879\u68c0\u67e5\u66f4\u5feb\u3002\u5178\u578b\u7684\u5b9e\u73b0\u53ef\u4ee5\u662f\u54c8\u5e0c\u8868\uff08o(1) \u67e5\u627e\uff09\u6216\u641c\u7d22\u6811\uff08o(log(n)) \u67e5\u627e\uff09\u3002<\/p>\n<p><strong>\u8981\u70b9<\/strong><\/p>\n<ul>\n<li>\u5feb\u901f\u8bbf\u95ee\uff1a\u96c6\u5408\u63d0\u4f9b\u5bf9\u5143\u7d20\u7684\u5feb\u901f\u8bbf\u95ee\u3002<\/li>\n<li>\u5b9e\u73b0\uff1a\u901a\u5e38\u4f7f\u7528\u54c8\u5e0c\u8868\u6216\u641c\u7d22\u6811\u6765\u5b9e\u73b0\u3002<\/li>\n<li>\u67e5\u627e\u65f6\u95f4\uff1a\u5e73\u5747\u67e5\u627e\u65f6\u95f4\u4f18\u4e8e o(n)\uff0c\u901a\u5e38 <strong>o(1) \u6216 o(log(n))<\/strong>\u3002<\/li>\n<\/ul>\n<hr>\n<p><strong>\u57fa\u672c\u65b9\u6cd5<\/strong><\/p>\n<ol>\n<li>add \uff1a\u5b83\u5c06\u6dfb\u52a0\u5143\u7d20\u5230\u96c6\u5408\u4e2d\u3002\u5982\u679c\u8be5\u5143\u7d20\u5b58\u5728\u4e8e\u96c6\u5408\u4e2d\uff0c\u5b83\u5c06\u4e0d\u4f1a\u6267\u884c\u4efb\u4f55\u64cd\u4f5c\u3002<\/li>\n<li>has \uff1a\u5982\u679c\u5143\u7d20\u5b58\u5728\u4e8e\u96c6\u5408\u4e2d\uff0c\u5219\u8fd4\u56de true\uff0c\u5426\u5219\u8fd4\u56de false\u3002 <\/li>\n<li>size \uff1a\u5b83\u5c06\u8fd4\u56de\u96c6\u5408\u7684\u5927\u5c0f\u3002 <\/li>\n<li>delete \uff1a\u5c06\u4ece\u96c6\u5408\u4e2d\u5220\u9664\u5143\u7d20\u3002 <\/li>\n<li>keys \uff1ajavascript set \u4e2d\u7684 .keys() \u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u8fed\u4ee3\u5668\u5bf9\u8c61\uff0c\u5176\u4e2d\u5305\u542b\u6309\u63d2\u5165\u987a\u5e8f\u6392\u5217\u7684 set \u503c\u3002 <\/li>\n<\/ol>\n<p><strong>\u793a\u4f8b<\/strong><\/p>\n<pre>\/\/ 1. create a new set and use the .add() method to add elements\nconst myset = new set();\nmyset.add(10);\nmyset.add(20);\nmyset.add(30);\n\nconsole.log(myset); \/\/ output: set { 10, 20, 30 }\n\n\/\/ 2. check if the set has a specific element using .has() method\nconsole.log(myset.has(20)); \/\/ output: true\nconsole.log(myset.has(40)); \/\/ output: false\n\n\/\/ 3. delete an element from the set using .delete() method\nmyset.delete(20);\nconsole.log(myset); \/\/ output: set { 10, 30 }\n\n\/\/ 4. iterate over the set using .keys() method\n\/\/ in sets, .keys() and .values() do the same thing\nfor (const key of myset.keys()) {\n  console.log(key);\n}\n\/\/ output:\n\/\/ 10\n\/\/ 30\n\n\/\/ 5. get the size of the set using .size property\nconsole.log(myset.size); \/\/ output: 2\n\n<\/pre>\n<hr>\n<p><em><strong>leetcode\u95ee\u9898\u8bbe\u7f6e\u793a\u4f8b\uff1a<\/strong><\/em><\/p>\n<p>3.\u6ca1\u6709\u91cd\u590d\u5b57\u7b26\u7684\u6700\u957f\u5b50\u4e32<\/p>\n<p>\u7ed9\u5b9a\u4e00\u4e2a\u5b57\u7b26\u4e32 s\uff0c\u627e\u5230\u6700\u957f\u7684\u4e0d\u5305\u542b\u91cd\u590d\u5b57\u7b26\u7684\u5b50\u4e32\u7684\u957f\u5ea6\u3002<\/p>\n<p><strong>\u89e3\u51b3\u65b9\u6848<\/strong><\/p>\n<pre>\/**\n * @param {string} s\n * @return {number}\n *\/\nvar lengthOfLongestSubstring = function(s) {\n    let set = new Set();\n    let ans = 0;\n    let s_index = 0;\n    for (let i = 0; i &lt; s.length; i++) {\n        if (!set.has(s[i])) {\n            set.add(s[i]);\n            ans = Math.max(ans, set.size);\n        } else {\n            while (s_index &lt; i &amp;&amp; set.has(s[i])) {\n                set.delete(s[s_index++]);\n            }\n            set.add(s[i]);\n            ans = Math.max(ans, set.size);\n        }\n    }\n    return ans;\n};\n\n\/* \nExample 1:\n\nInput: s = \"abcabcbb\"\nOutput: 3\nExplanation: The answer is \"abc\", with the length of 3.\nExample 2:\n\nInput: s = \"bbbbb\"\nOutput: 1\nExplanation: The answer is \"b\", with the length of 1.\nExample 3:\n\nInput: s = \"pwwkew\"\nOutput: 3\nExplanation: The answer is \"wke\", with the length of 3.\nNotice that the answer must be a substring, \"pwke\" is a subsequence and not a substring.\n*\/\n<\/pre>\n<p>\u8bf4\u660e\uff1a<br \/> \u51fd\u6570 lengthoflongestsubstring \u4f7f\u7528\u5e26\u6709 set \u7684\u6ed1\u52a8\u7a97\u53e3\u6280\u672f\u6765\u67e5\u627e\u4e0d\u91cd\u590d\u5b57\u7b26\u7684\u6700\u957f\u5b50\u5b57\u7b26\u4e32\uff1a<\/p>\n<ul>\n<li>\u6269\u5c55\u7a97\u53e3\uff1a\u5982\u679c\u89d2\u8272\u5c1a\u4e0d\u5b58\u5728\uff0c\u8bf7\u5c06\u5176\u6dfb\u52a0\u5230\u96c6\u5408\u4e2d\u3002<\/li>\n<li>\u7f29\u5c0f\u7a97\u53e3\uff1a\u5f53\u53d1\u73b0\u91cd\u590d\u9879\u65f6\uff0c\u4ece\u7a97\u53e3\u5f00\u5934\u5220\u9664\u5b57\u7b26\uff0c\u8c03\u6574\u7a97\u53e3\u5927\u5c0f\u3002<\/li>\n<li>\u66f4\u65b0\u957f\u5ea6\uff1a\u8ddf\u8e2a\u5177\u6709\u552f\u4e00\u5b57\u7b26\u7684\u5b50\u5b57\u7b26\u4e32\u7684\u6700\u5927\u957f\u5ea6\u3002<\/li>\n<li>\u8be5\u65b9\u6cd5\u901a\u8fc7\u6700\u591a\u5904\u7406\u6bcf\u4e2a\u5b57\u7b26\u4e24\u6b21\u6765\u786e\u4fdd\u9ad8\u6548\u7684 o(n) \u65f6\u95f4\u590d\u6742\u5ea6\u3002<\/li>\n<\/ul>\n<p>\u5c31\u662f\u8fd9\u6837\uff0c\u5982\u679c\u60a8\u6709\u4efb\u4f55\u7591\u95ee\u6216\u4efb\u4f55\u5efa\u8bae\u6216\u4efb\u4f55\u4e8b\u60c5\uff0c\u8bf7\u968f\u65f6\u6dfb\u52a0\u8bc4\u8bba\u3002 <\/p>\n<p>\u6765\u6e90\uff1a<br \/> mdn\uff08\u96c6\uff09<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662f\u300aJavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09\u300b\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u5173\u4e8e\u7684\u8d44\u6599\u8bf7\u5173\u6ce8\u7c73\u4e91\u516c\u4f17\u53f7\uff01<\/p>\n<p>      \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb\u5220\u9664    <\/p>\n<dl>\n<dt><\/dt>\n<dd>\n   \u89e3\u51b3\u7535\u8111\u6545\u969c\u7684\u6700\u4f73\u52a9\u624b &#8211; \u7535\u8111\u6545\u969c\u4e00\u67e5\u901aAPP\n <\/dd>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"<p>JavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09 \u6536\u85cf \u4eca\u5929\u7c73\u4e91\u7ed9\u5927\u5bb6\u5e26\u6765\u4e86\u300aJavaScript \u4e2d\u7684 SET\uff08\u521d\u5b66\u8005\u6559\u7a0b\uff09\u300b\uff0c\u5176\u4e2d\u6d89\u53ca\u5230\u7684\u77e5\u8bc6\u70b9\u5305\u62ec\u7b49\u7b49\uff0c\u65e0\u8bba\u4f60\u662f\u5c0f\u767d\u8fd8\u662f\u8001\u624b\uff0c\u90fd\u9002\u5408\u770b\u4e00\u770b\u54e6~\u6709\u597d\u7684\u5efa\u8bae\u4e5f\u6b22\u8fce\u5927\u5bb6\u5728\u8bc4\u8bba\u7559\u8a00\uff0c\u82e5\u662f\u770b\u5b8c\u6709\u6240\u6536\u83b7\uff0c\u4e5f\u5e0c\u671b\u5927\u5bb6\u80fd\u591a\u591a\u70b9\u8d5e\u652f\u6301\u5440\uff01\u4e00\u8d77\u52a0\u6cb9\u5b66\u4e60~ \u4f60\u597d\uff0c \u60a8\u662f\u5426\u6b63\u5728\u5bfb\u627e\u4e00\u79cd\u5b58\u50a8\u552f\u4e00\u503c\u3001\u5141\u8bb8\u63d2\u5165\u503c\u3001\u67e5\u627e\u503c\u603b\u6570\u548c\u5220\u9664\u503c\u7684\u6570\u636e\u7ed3\u6784\uff1f\u5957\u88c5\u662f\u6700\u4f73\u9009\u62e9\u3002\u8bb8\u591a\u7f16\u7a0b\u8bed\u8a00\u90fd\u5305\u542b\u5185\u7f6e\u7684 set \u6570\u636e\u7ed3\u6784\uff0cjavascript \u4e5f\u4e0d\u4f8b\u5916\u3002\u8ba9\u6211\u4eec\u66f4\u6df1\u5165\u5730\u4e86\u89e3\u96c6\u5408\u7684\u5de5\u4f5c\u539f\u7406\u3002 \u8bbe\u7f6e\u662f\u4ec0\u4e48\uff1f \u200b\u200b set \u662f\u4e00\u79cd\u6570\u636e\u7ed3\u6784\uff0c\u53ef\u8ba9\u60a8\u5b58\u50a8\u4efb\u4f55\u7c7b\u578b\u7684\u552f\u4e00\u503c\uff0c\u65e0\u8bba\u662f\u539f\u59cb\u503c\u8fd8\u662f\u5bf9\u8c61\u5f15\u7528\u3002\u8be5\u96c6\u5408\u5141\u8bb8\u6267\u884c o(1) \u65f6\u95f4\u590d\u6742\u5ea6\u7684\u63d2\u5165\u3001\u5220\u9664\u3001\u66f4\u65b0\u548c\u5927\u5c0f\u64cd\u4f5c\u3002\u8fd9\u4f7f\u5f97\u8bbe\u7f6e\u66f4\u5feb\u3001\u66f4\u9ad8\u6548\u3002 \u5957\u88c5\u65e8\u5728\u63d0\u4f9b\u5feb\u901f\u8bbf\u95ee\u65f6\u95f4\u3002\u5b83\u4eec\u7684\u5b9e\u73b0\u65b9\u5f0f\u901a\u5e38\u4f7f\u67e5\u627e\u9879\u76ee\u6bd4\u7b80\u5355\u5730\u9010\u9879\u68c0\u67e5\u66f4\u5feb\u3002\u5178\u578b\u7684\u5b9e\u73b0\u53ef\u4ee5\u662f\u54c8\u5e0c\u8868\uff08o(1) \u67e5\u627e\uff09\u6216\u641c\u7d22\u6811\uff08o(log(n)) \u67e5\u627e\uff09\u3002 \u8981\u70b9 \u5feb\u901f\u8bbf\u95ee\uff1a\u96c6\u5408\u63d0\u4f9b\u5bf9\u5143\u7d20\u7684\u5feb\u901f\u8bbf\u95ee\u3002 \u5b9e\u73b0\uff1a\u901a\u5e38\u4f7f\u7528\u54c8\u5e0c\u8868\u6216\u641c\u7d22\u6811\u6765\u5b9e\u73b0\u3002 \u67e5\u627e\u65f6\u95f4\uff1a\u5e73\u5747\u67e5\u627e\u65f6\u95f4\u4f18\u4e8e o(n)\uff0c\u901a\u5e38 o(1) \u6216 o(log(n))\u3002 \u57fa\u672c\u65b9\u6cd5 add \uff1a\u5b83\u5c06\u6dfb\u52a0\u5143\u7d20\u5230\u96c6\u5408\u4e2d\u3002\u5982\u679c\u8be5\u5143\u7d20\u5b58\u5728\u4e8e\u96c6\u5408\u4e2d\uff0c\u5b83\u5c06\u4e0d\u4f1a\u6267\u884c\u4efb\u4f55\u64cd\u4f5c\u3002 has \uff1a\u5982\u679c\u5143\u7d20\u5b58\u5728\u4e8e\u96c6\u5408\u4e2d\uff0c\u5219\u8fd4\u56de true\uff0c\u5426\u5219\u8fd4\u56de false\u3002 size \uff1a\u5b83\u5c06\u8fd4\u56de\u96c6\u5408\u7684\u5927\u5c0f\u3002 delete \uff1a\u5c06\u4ece\u96c6\u5408\u4e2d\u5220\u9664\u5143\u7d20\u3002 keys \uff1ajavascript set \u4e2d\u7684 .keys() \u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u8fed\u4ee3\u5668\u5bf9\u8c61\uff0c\u5176\u4e2d\u5305\u542b\u6309\u63d2\u5165\u987a\u5e8f\u6392\u5217\u7684 set \u503c\u3002 \u793a\u4f8b \/\/ 1. create a new set [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-53052","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/53052","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=53052"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/53052\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=53052"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=53052"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=53052"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}