A sentence is a list of words that are separated by a single space with no leading or trailing spaces.

You are given an array of strings `sentences`, where each `sentences[i]` represents a single sentence.

Return the maximum number of words that appear in a single sentence.

Example 1:

    Input: sentences = ["alice and bob love leetcode", "i think so too", "this is great thanks very much"]
    Output: 6
    Explanation:
    - The first sentence, "alice and bob love leetcode", has 5 words in total.
    - The second sentence, "i think so too", has 4 words in total.
    - The third sentence, "this is great thanks very much", has 6 words in total.
    Thus, the maximum number of words in a single sentence comes from the third sentence, which has 6 words.

Example 2:

    Input: sentences = ["please wait", "continue to fight", "continue to win"]
    Output: 3
    Explanation: It is possible that multiple sentences contain the same number of words.
    In this example, the second and third sentences (underlined) have the same number of words.

Constraints:

- `1 <= sentences.length <= 100`
- `1 <= sentences[i].length <= 100`
- `sentences[i]` consists only of lowercase English letters and `' '` only.
- `sentences[i]` does not have leading or trailing spaces.
- All the words in `sentences[i]` are separated by a single space.