{"id":3005,"date":"2020-02-20T11:10:58","date_gmt":"2020-02-20T03:10:58","guid":{"rendered":"http:\/\/www.sniper97.cn\/?p=3005"},"modified":"2020-02-20T11:10:58","modified_gmt":"2020-02-20T03:10:58","slug":"%e3%80%90leetcode%e3%80%910060-%e7%ac%ack%e4%b8%aa%e6%8e%92%e5%88%97","status":"publish","type":"post","link":"http:\/\/www.sniper97.cn\/index.php\/note\/algorithm\/3005\/","title":{"rendered":"\u3010LeetCode\u3011*0060 \u7b2ck\u4e2a\u6392\u5217"},"content":{"rendered":"\n<p><a href=\"https:\/\/leetcode-cn.com\/problems\/permutation-sequence\/\">https:\/\/leetcode-cn.com\/problems\/permutation-sequence\/<\/a><\/p>\n\n\n<pre class=\"wp-block-preformatted\"># -*- coding:utf-8 -*-\n<em>\n<\/em>class Solution(object):\n    def getPermutation(self, n, k):\n        <em>\"\"\"\n        <\/em><strong><em>:type<\/em><\/strong><em> n: int\n        <\/em><strong><em>:type<\/em><\/strong><em> k: int\n        <\/em><strong><em>:rtype<\/em><\/strong><em>: str\n        \"\"\"\n        <\/em>def back(i, flag_list, temp_list=[]):\n            <em>\"\"\"\n            \u56de\u6eaf\n            <\/em><strong><em>:return<\/em><\/strong><em>:\n            \"\"\"\n            <\/em>if i == n:\n                output.append(temp_list)\n                return\n            for j in range(len(flag_list)):\n                if flag_list[j] != 0:\n                    flag_list[j] = 0\n                    temp_list.append(j + 1)\n                    back(i + 1, flag_list[:], temp_list[:])\n                    flag_list[j] = 1\n                    temp_list = temp_list[:-1]\n        output = []\n        flag_list = [1 for _ in range(n)]\n        back(0, flag_list)\n        res = ''\n        for each in output[k-1]:\n            res = res+str(each)\n        return res\nif __name__ == '__main__':\n    n = 3\n    k = 3\n    print(Solution().getPermutation(n, k))\n<\/pre>\n\n\n<p><strong>\u601d\u8def<\/strong>\uff1a\u56de\u6eaf\uff0c\u548c\u524d\u9762\u6bd4\u8f83\u50cf\u3002<\/p>\n\n\n<p>\u4f46\u662f\u8fd9\u9053\u9898\u5b66\u5230\u4e86\u4e00\u4e2a\u65b0\u4e1c\u897f\uff0c<strong><a rel=\"noreferrer noopener\" aria-label=\"\u5eb7\u6258\u5c55\u5f00\uff08\u5728\u65b0\u7a97\u53e3\u6253\u5f00\uff09\" href=\"https:\/\/baike.baidu.com\/item\/%E5%BA%B7%E6%89%98%E5%B1%95%E5%BC%80\/7968428?fr=aladdin\" target=\"_blank\">\u5eb7\u6258\u5c55\u5f00<\/a><\/strong>\uff0c\u8fd9\u4e1c\u897f\u4e5f\u592a\u5f3a\u4e86\uff0c\u53ef\u4ee5\u76f4\u63a5\u7b97\u51fa\u7ed3\u679c\u3002<\/p>\n\n\n<pre class=\"wp-block-code\"><code>chs = [i for i in range(1, 10)]\n        factor = [1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880]\n        k -= 1\n        ans = ''\n        for i in range(n - 1, -1, -1):\n            j, k = divmod(k, factor[i])\n            ans += str(chs.pop(j))\n        return ans<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>https:\/\/leetcode-cn.com\/problems\/permutation-seque [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_mi_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[10],"tags":[],"views":1837,"_links":{"self":[{"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/posts\/3005"}],"collection":[{"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/comments?post=3005"}],"version-history":[{"count":0,"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/posts\/3005\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/media?parent=3005"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/categories?post=3005"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.sniper97.cn\/index.php\/wp-json\/wp\/v2\/tags?post=3005"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}