[Swift]LeetCode434. 字符串中的單詞數 | Number of Segments in a String

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Count the number of segments in a string, where a segment is defined to be a contiguous sequence of non-space characters.

Please note that the string does not contain any non-printable characters.

Example:

Input: "Hello, my name is John"
Output: 5

---

統計字符串中的單詞個數，這裏的單詞指的是連續的不是空格的字符。

請注意，你能夠假定字符串裏不包括任何不可打印的字符。

示例:

輸入: "Hello, my name is John"
輸出: 5

---

8ms

 1 class Solution {
 2     func countSegments(_ s: String) -> Int {
 3         if s == nil || s.count == 0 {return 0}
 4         var word:Int = 0
 5         var count:Int = 0
 6         //按索引遍歷
 7         for i in s.indices
 8         {
 9             if s[i] == " "
10             {
11                 if word > 0
12                 {
13                     count += 1
14                     word = 0
15                 }
16             }
17             else
18             {
19                 word += 1
20             }            
21         }
22         if word > 0
23         {
24             count += 1
25         }
26         return count
27     }
28 }

---

8ms

 1 class Solution {
 2     func countSegments(_ s: String) -> Int {
 3         var count = 0
 4         var segmentInProgress = false
 5         for char in s {
 6             if char != " " && !segmentInProgress {
 7                 count += 1
 8                 segmentInProgress = true
 9             } else if char == " " {
10                 segmentInProgress = false
11             }
12         }
13         
14         return count
15     }
16 }

---

12ms

1 class Solution {
2     func countSegments(_ s: String) -> Int {
3         return s.split(separator: " ").count
4     }
5 }

---

16ms

1 class Solution {
2     func countSegments(_ s: String) -> Int {
3         return s.characters.split(separator: " ").count
4     }
5 }