Number of Segments in a String

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434.Number of Segments in a String

Given a string s, return the number of segments in the string.

A segment is defined to be a contiguous sequence of non-space characters.

Example 1:

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Input: s = "Hello, my name is John"
Output: 5
Explanation: The five segments are ["Hello,", "my", "name", "is", "John"]

Example 2:

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Input: s = "Hello"
Output: 1

上锁：

时间复杂度：O(n)

空间复杂度：O(1)

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class Solution {
public:
    int countSegments(string s) {
        int ans = 0;
        bool flag = true;
        for (char ch : s) {
            if (ch != ' ' && flag) {
                ans++;
                flag = false;
            }
            if (ch == ' ')flag = true;
        }
        return ans;
    }
};

原地法：

时间复杂度：O(n)

空间复杂度：O(1)

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class Solution {
public:
    int countSegments(string s) {
        int segmentCount = 0;

        for (int i = 0; i < s.size(); i++) {
            if ((i == 0 || s[i - 1] == ' ') && s[i] != ' ') {
                segmentCount++;
            }
        }

        return segmentCount;
    }
};