Question

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

中文文档

Description

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.

Solutions

Solution 1

class Solution:
  def isPrefixOfWord(self, sentence: str, searchWord: str) -> int:
    for i, s in enumerate(sentence.split(), 1):
      if s.startswith(searchWord):
        return i
    return -1

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;
  }
}

class Solution {
public:
  int isPrefixOfWord(string sentence, string searchWord) {
    stringstream ss(sentence);
    string s;
    for (int i = 1; ss >> s; ++i) {
      if (s.find(searchWord) == 0) {
        return i;
      }
    }
    return -1;
  }
};

func isPrefixOfWord(sentence string, searchWord string) int {
  for i, s := range strings.Split(sentence, " ") {
    if strings.HasPrefix(s, searchWord) {
      return i + 1
    }
  }
  return -1
}

function isPrefixOfWord(sentence: string, searchWord: string): number {
  const ss = sentence.split(/\s/);
  const n = ss.length;
  for (let i = 0; i < n; i++) {
    if (ss[i].startsWith(searchWord)) {
      return i + 1;
    }
  }
  return -1;
}

impl Solution {
  pub fn is_prefix_of_word(sentence: String, search_word: String) -> i32 {
    let ss = sentence.split_whitespace().collect::<Vec<&str>>();
    for i in 0..ss.len() {
      if ss[i].starts_with(&search_word) {
        return (i + 1) as i32;
      }
    }
    -1
  }
}

class Solution {
  /**
   * @param String $sentence
   * @param String $searchWord
   * @return Integer
   */
  function isPrefixOfWord($sentence, $searchWord) {
    $arr = explode(' ', $sentence);
    for ($i = 0; $i < count($arr); $i++) {
      if (strpos($arr[$i], $searchWord) === 0) {
        return $i + 1;
      }
    }
    return -1;
  }
}