1078. Occurrences After Bigram

Given words first and second, consider occurrences in some text of the form "first second third", where second comes immediately after first, and third comes immediately after second.

For each such occurrence, add "third" to the answer, and return the answer.

 

Example 1:

Input: text = "alice is a good girl she is a good student", first = "a", second = "good"
Output: ["girl","student"]

Example 2:

Input: text = "we will we will rock you", first = "we", second = "will"
Output: ["we","rock"]

 

Note:

  1. 1 <= text.length <= 1000
  2. text consists of space separated words, where each word consists of lowercase English letters.
  3. 1 <= first.length, second.length <= 10
  4. first and second consist of lowercase English letters.

Rust Solution

struct Solution;

impl Solution {
    fn find_ocurrences(text: String, first: String, second: String) -> Vec<String> {
        let mut res: Vec<String> = vec![];
        let words: Vec<&str> = text.split_whitespace().collect();
        words.windows(3).for_each(|v| {
            if v[0] == first && v[1] == second {
                res.push(v[2].to_string());
            }
        });
        res
    }
}

#[test]
fn test() {
    let text = "alice is a good girl she is a good student".to_string();
    let first = "a".to_string();
    let second = "good".to_string();
    let res: Vec<String> = vec_string!["girl", "student"];
    assert_eq!(Solution::find_ocurrences(text, first, second), res);
    let text = "we will we will rock you".to_string();
    let first = "we".to_string();
    let second = "will".to_string();
    let res: Vec<String> = vec_string!["we", "rock"];
    assert_eq!(Solution::find_ocurrences(text, first, second), res);
}

Having problems with this solution? Click here to submit an issue on github.