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10. Regular Expression Matching字符串.*匹配

ive eating 空間 ati HA imp string pty con

[抄題]:

Given an input string (s) and a pattern (p), implement regular expression matching with support for ‘.‘ and ‘*‘.

‘.‘ Matches any single character.
‘*‘ Matches zero or more of the preceding element.

The matching should cover the entire input string (not partial).

Note:

  • s could be empty and contains only lowercase letters a-z
    .
  • p could be empty and contains only lowercase letters a-z, and characters like . or *.

Example 1:

Input:
s = "aa"
p = "a"
Output: false
Explanation: "a" does not match the entire string "aa".

Example 2:

Input:
s = "aa"
p = "a*"
Output: true
Explanation: ‘*‘ means zero or more of the precedeng element, ‘a‘. Therefore, by repeating ‘a‘ once, it becomes "aa".

Example 3:

Input:
s = "ab"
p = ".*"
Output: true
Explanation: ".*" means "zero or more (*) of any character (.)".

Example 4:

Input:
s = "aab"
p = "c*a*b"
Output: true
Explanation: c can be repeated 0 times, a can be repeated 1 time. Therefore it matches "aab".

Example 5:

Input:
s = "mississippi"
p = "mis*is*p*."
Output: false

[暴力解法]:

時間分析:

空間分析:

[優化後]:

時間分析:

空間分析:

[奇葩輸出條件]:

[奇葩corner case]:

[思維問題]:

想不到是dp:最值、可行、個數

[一句話思路]:

[輸入量]:空: 正常情況:特大:特小:程序裏處理到的特殊情況:異常情況(不合法不合理的輸入):

[畫圖]:

[一刷]:

[二刷]:

[三刷]:

[四刷]:

[五刷]:

[五分鐘肉眼debug的結果]:

[總結]:

[復雜度]:Time complexity: O() Space complexity: O()

[英文數據結構或算法,為什麽不用別的數據結構或算法]:

[關鍵模板化代碼]:

[其他解法]:

[Follow Up]:

[LC給出的題目變變變]:

[代碼風格] :

10. Regular Expression Matching字符串.*匹配