{"id":9703,"date":"2022-04-30T22:25:24","date_gmt":"2022-05-01T05:25:24","guid":{"rendered":"https:\/\/zxi.mytechroad.com\/blog\/?p=9703"},"modified":"2022-04-30T22:26:49","modified_gmt":"2022-05-01T05:26:49","slug":"leetcode-2255-count-prefixes-of-a-given-string","status":"publish","type":"post","link":"https:\/\/zxi.mytechroad.com\/blog\/string\/leetcode-2255-count-prefixes-of-a-given-string\/","title":{"rendered":"\u82b1\u82b1\u9171 LeetCode 2255. Count Prefixes of a Given String"},"content":{"rendered":"\n

You are given a string array words<\/code> and a string s<\/code>, where words[i]<\/code> and s<\/code> comprise only of lowercase English letters<\/strong>.<\/p>\n\n\n\n

Return the number of strings<\/strong> in<\/em> words<\/code> that are a prefix<\/strong> of<\/em> s<\/code>.<\/p>\n\n\n\n

A prefix<\/strong> of a string is a substring that occurs at the beginning of the string. A substring<\/strong> is a contiguous sequence of characters within a string.<\/p>\n\n\n\n

Example 1:<\/strong><\/p>\n\n\n\n

Input:<\/strong> words = [\"a\",\"b\",\"c\",\"ab\",\"bc\",\"abc\"], s = \"abc\"\nOutput:<\/strong> 3\nExplanation:<\/strong>\nThe strings in words which are a prefix of s = \"abc\" are:\n\"a\", \"ab\", and \"abc\".\nThus the number of strings in words which are a prefix of s is 3.<\/pre>\n\n\n\n
Example 2:<\/strong><\/p>\n\n\n\n
Input:<\/strong> words = [\"a\",\"a\"], s = \"aa\"\nOutput:<\/strong> 2\nExplanation:\n<\/strong>Both of the strings are a prefix of s. \nNote that the same string can occur multiple times in words, and it should be counted each time.<\/pre>\n\n\n\n
Constraints:<\/strong><\/p>\n\n\n\n
  • 1 <= words.length <= 1000<\/code><\/li>
  • 1 <= words[i].length, s.length <= 10<\/code><\/li>
  • words[i]<\/code> and s<\/code> consist of lowercase English letters only<\/strong>.<\/li><\/ul>\n\n\n\n
    Solution: Brute Force<\/strong><\/h2>\n\n\n\n
    Time complexity: O(n*m)
    Space complexity: O(1)<\/p>\n\n\n\n
    \n
    C++<\/h2>\n
    \n\n
    \n\/\/ Author: Huahua\nclass Solution {\npublic:\n  int countPrefixes(vector& words, string s) {\n    return count_if(begin(words), end(words), [&s](const string& word) {\n      return s.find(word) == 0;\n    });\n  }\n};\n<\/pre>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"
    You are given a string array words and a string s, where words[i] and s comprise only of lowercase English letters. Return the number of strings in words that are a prefix of s. A prefix of a string is a substring that…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[47],"tags":[222,4],"class_list":["post-9703","post","type-post","status-publish","format-standard","hentry","category-string","tag-easy","tag-string","entry","simple"],"_links":{"self":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/9703","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/comments?post=9703"}],"version-history":[{"count":2,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/9703\/revisions"}],"predecessor-version":[{"id":9705,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/9703\/revisions\/9705"}],"wp:attachment":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/media?parent=9703"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/categories?post=9703"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/tags?post=9703"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}