{"id":2886,"date":"2018-06-03T09:41:27","date_gmt":"2018-06-03T16:41:27","guid":{"rendered":"http:\/\/zxi.mytechroad.com\/blog\/?p=2886"},"modified":"2018-09-04T09:16:13","modified_gmt":"2018-09-04T16:16:13","slug":"leetcode-844-backspace-string-compare","status":"publish","type":"post","link":"https:\/\/zxi.mytechroad.com\/blog\/string\/leetcode-844-backspace-string-compare\/","title":{"rendered":"\u82b1\u82b1\u9171 LeetCode 844. Backspace String Compare"},"content":{"rendered":"

Problem<\/strong><\/h1>\n

\u9898\u76ee\u5927\u610f\uff1a\u7ed9\u4f602\u4e2a\u5b57\u7b26\u4e32\u8868\u793a\u6253\u5b57\u987a\u5e8f\uff0c\u5224\u65ad\u5b83\u4eec\u7684\u7ed3\u679c\u662f\u5426\u76f8\u540c\uff0c’#’\u8868\u793a\u9000\u683c\u952e\u3002<\/p>\n

https:\/\/leetcode.com\/problems\/backspace-string-compare\/description\/<\/a><\/p>\n

Given two\u00a0strings\u00a0S<\/code>\u00a0and\u00a0T<\/code>,\u00a0return if they are equal when both are typed into empty text editors.\u00a0#<\/code>\u00a0means a backspace character.<\/p>\n

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

Input: <\/strong>S = \"ab#c\"<\/span>, T = \"ad#c\"<\/span>\r\nOutput: <\/strong>true\r\n<\/span>Explanation<\/strong>: Both S and T become \"ac\".\r\n<\/pre>\n
Example 2:<\/strong><\/p>\n
Input: <\/strong>S = \"ab##\"<\/span>, T = \"c#d#\"<\/span>\r\nOutput: <\/strong>true\r\n<\/span>Explanation<\/strong>: Both S and T become \"\".\r\n<\/pre>\n
Example 3:<\/strong><\/p>\n
Input: <\/strong>S = \"a##c\"<\/span>, T = \"#a#c\"<\/span>\r\nOutput: <\/strong>true\r\n<\/span>Explanation<\/strong>: Both S and T become \"c\".\r\n<\/pre>\n
Example 4:<\/strong><\/p>\n
Input: <\/strong>S = \"a#c\"<\/span>, T = \"b\"<\/span>\r\nOutput: <\/strong>false\r\n<\/span>Explanation<\/strong>: S becomes \"c\" while T becomes \"b\".\r\n<\/pre>\n
Note<\/strong>:<\/p>\n
    \n
  1. 1 <= S.length <= 200<\/code><\/li>\n
  2. 1 <= T.length <= 200<\/code><\/li>\n
  3. S<\/code>\u00a0and\u00a0T<\/code>\u00a0only contain\u00a0lowercase letters and\u00a0'#'<\/code>\u00a0characters.<\/li>\n<\/ol>\n
    \u00a0<\/ins><\/p>\n
    Solution: Simulation<\/h1>\n
    Time complexity: O(|S| + |T|)<\/p>\n
    Space complexity: O(|S| + |T|)<\/p>\n
    \n
    C++<\/h2>\n
    \n\n
    \/\/ Author: Huahua\r\n\/\/ Running time: 5 ms\r\nclass Solution {\r\npublic:\r\n  bool backspaceCompare(string S, string T) {\r\n    return type(S) == type(T);\r\n  }\r\nprivate:\r\n  string type(string S) {\r\n    string o;\r\n    for (char c : S)\r\n      if (c == '#') {\r\n        if (!o.empty()) \r\n        o.pop_back();\r\n      } else {\r\n        o.push_back(c);\r\n      }\r\n    return o;\r\n  }\r\n};<\/pre>\n\n<\/div>
    Java<\/h2>\n
    \n\n
    \/\/ Author: Huahua, 7 ms\r\nclass Solution {\r\n  public boolean backspaceCompare(String S, String T) {\r\n    return type(S).equals(type(T));\r\n  }\r\n  \r\n  private String type(String s) {\r\n    StringBuilder sb = new StringBuilder();\r\n    for (char c : s.toCharArray()) {\r\n      if (c == '#') {\r\n        if (sb.length() > 0)\r\n          sb.setLength(sb.length() - 1);\r\n      } else {\r\n        sb.append(c);\r\n      }\r\n    }\r\n    return sb.toString();\r\n  }\r\n}<\/pre>\n\n<\/div>
    Python3<\/h2>\n
    \n\n
    # Author: Huahua, 40 ms\r\nclass Solution:\r\n  def backspaceCompare(self, S, T):\r\n    def sim(S):\r\n      ans = ''\r\n      for c in S:\r\n        if c == '#':\r\n          if len(ans) > 0: ans = ans[:-1]\r\n        else:\r\n          ans += c\r\n      return ans\r\n    return sim(S) == sim(T)<\/pre>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"
    Problem \u9898\u76ee\u5927\u610f\uff1a\u7ed9\u4f602\u4e2a\u5b57\u7b26\u4e32\u8868\u793a\u6253\u5b57\u987a\u5e8f\uff0c\u5224\u65ad\u5b83\u4eec\u7684\u7ed3\u679c\u662f\u5426\u76f8\u540c\uff0c’#’\u8868\u793a\u9000\u683c\u952e\u3002 https:\/\/leetcode.com\/problems\/backspace-string-compare\/description\/ Given two\u00a0strings\u00a0S\u00a0and\u00a0T,\u00a0return if they are equal when both are typed into empty text editors.\u00a0#\u00a0means a backspace character. Example 1: Input: S =…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48,47],"tags":[222,179,180,4],"class_list":["post-2886","post","type-post","status-publish","format-standard","hentry","category-simulation","category-string","tag-easy","tag-simulation","tag-stack","tag-string","entry","simple"],"_links":{"self":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/2886","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=2886"}],"version-history":[{"count":5,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/2886\/revisions"}],"predecessor-version":[{"id":3867,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/2886\/revisions\/3867"}],"wp:attachment":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/media?parent=2886"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/categories?post=2886"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/tags?post=2886"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}