1455. Check If a Word Occurs As a Prefix of Any Word in a Sentence

Problem

Given a sentence that consists of some words separated by a single space, and a searchWord, check if searchWord is a prefix of any word in sentence.

Return **the index of the word in *sentence* (1-indexed) where searchWord is a prefix of this word**. If searchWord is a prefix of more than one word, return the index of the first word *(minimum index)*. If there is no such word return -1.

A prefix of a string s is any leading contiguous substring of s.

  Example 1:

Input: sentence = "i love eating burger", searchWord = "burg"
Output: 4
Explanation: "burg" is prefix of "burger" which is the 4th word in the sentence.

Example 2:

Input: sentence = "this problem is an easy problem", searchWord = "pro"
Output: 2
Explanation: "pro" is prefix of "problem" which is the 2nd and the 6th word in the sentence, but we return 2 as it's the minimal index.

Example 3:

Input: sentence = "i am tired", searchWord = "you"
Output: -1
Explanation: "you" is not a prefix of any word in the sentence.

  Constraints:

• 1 <= sentence.length <= 100

• 1 <= searchWord.length <= 10

• sentence consists of lowercase English letters and spaces.

• searchWord consists of lowercase English letters.

Solution (Java)

class Solution {
    public int isPrefixOfWord(String sentence, String searchWord) {
        String[] words = sentence.split(" ");
        for (int i = 0; i < words.length; i++) {
            if (words[i].startsWith(searchWord)) {
                return i + 1;
            }
        }
        return -1;
    }
}

Explain:

nope.

Complexity:

• Time complexity : O(n).
• Space complexity : O(n).