Class Solution
Easy
A sentence consists of lowercase letters ('a'
to 'z'
), digits ('0'
to '9'
), hyphens ('-'
), punctuation marks ('!'
, '.'
, and ','
), and spaces (' '
) only. Each sentence can be broken down into one or more tokens separated by one or more spaces ' '
.
A token is a valid word if all three of the following are true:
- It only contains lowercase letters, hyphens, and/or punctuation ( no digits).
- There is at most one hyphen
'-'
. If present, it must be surrounded by lowercase characters ("a-b"
is valid, but"-ab"
and"ab-"
are not valid). - There is at most one punctuation mark. If present, it must be at the end of the token (
"ab,"
,"cd!"
, and"."
are valid, but"a!b"
and"c.,"
are not valid).
Examples of valid words include "a-b."
, "afad"
, "ba-c"
, "a!"
, and "!"
.
Given a string sentence
, return the number of valid words in sentence
.
Example 1:
Input: sentence = “cat and dog”
Output: 3
Explanation: The valid words in the sentence are “cat”, “and”, and “dog”.
Example 2:
Input: sentence = “!this 1-s b8d!”
Output: 0
Explanation: There are no valid words in the sentence.
“!this” is invalid because it starts with a punctuation mark.
“1-s” and “b8d” are invalid because they contain digits.
Example 3:
Input: sentence = “alice and bob are playing stone-game10”
Output: 5
Explanation: The valid words in the sentence are “alice”, “and”, “bob”, “are”, and “playing”. “stone-game10” is invalid because it contains digits.
Constraints:
1 <= sentence.length <= 1000
sentence
only contains lowercase English letters, digits,' '
,'-'
,'!'
,'.'
, and','
.- There will be at least
1
token.
-
Constructor Summary
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Method Summary
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
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Constructor Details
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Solution
public Solution()
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Method Details
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countValidWords
public int countValidWords(java.lang.String sentence)
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