1408. String Matching in an Array

Easy

Given an array of string words. Return all strings in words which is substring of another word in any order.

String words[i] is substring of words[j], if can be obtained removing some characters to left and/or right side of words[j].

Example 1:

Input: words = ["mass","as","hero","superhero"]
Output:
 ["as","hero"]
Explanation:
 "as" is substring of "mass" and "hero" is substring of "superhero".
["hero","as"] is also a valid answer.

Example 2:

Input: words = ["leetcode","et","code"]
Output:
 ["et","code"]
Explanation:
 "et", "code" are substring of "leetcode".

Example 3:

Input: words = ["blue","green","bu"]
Output:
 []

Constraints:

• 1 <= words.length <= 100

• 1 <= words[i].length <= 30

• words[i] contains only lowercase English letters.

• It's guaranteed that words[i] will be unique.

解題

Runtime: 3 ms, faster than 81.48%

Memory Usage: 2.4 MB, less than 70.37%

func stringMatching(words []string) []string {
    sort.Slice(words, func(i, j int) bool { return len(words[i]) > len(words[j]) })
    
    m := make(map[string]bool)
    ans := make([]string, 0)
    
    for i, word := range words {
        for j:=i+1; j<len(words); j++ {
            if strings.Contains(word, words[j]) {
                if !m[words[j]] {
                    ans = append(ans, words[j])
                    m[words[j]] = true
                }
            } 
        }
    }
    
    return ans
}