Package g0901_1000.s0953_verifying_an_alien_dictionary

Class Solution

  • public class Solution
extends Object
    953 - Verifying an Alien Dictionary.

    Easy

    In an alien language, surprisingly, they also use English lowercase letters, but possibly in a different order. The order of the alphabet is some permutation of lowercase letters.

    Given a sequence of words written in the alien language, and the order of the alphabet, return true if and only if the given words are sorted lexicographically in this alien language.

    Example 1:

    Input: words = [“hello”,“leetcode”], order = “hlabcdefgijkmnopqrstuvwxyz”

    Output: true

    Explanation: As ‘h’ comes before ‘l’ in this language, then the sequence is sorted.

    Example 2:

    Input: words = [“word”,“world”,“row”], order = “worldabcefghijkmnpqstuvxyz”

    Output: false

    Explanation: As ‘d’ comes after ‘l’ in this language, then words[0] > words[1], hence the sequence is unsorted.

    Example 3:

    Input: words = [“apple”,“app”], order = “abcdefghijklmnopqrstuvwxyz”

    Output: false

    Explanation: The first three characters “app” match, and the second string is shorter (in size.) According to lexicographical rules “apple” > “app”, because ‘l’ > ‘\u2205’, where ‘\u2205’ is defined as the blank character which is less than any other character (More info).

    Constraints:

    • 1 <= words.length <= 100
    • 1 <= words[i].length <= 20
    • order.length == 26
    • All characters in words[i] and order are English lowercase letters.

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • isAlienSorted

        public boolean isAlienSorted​(String[] words,
                             String order)