Package g2001_2100.s2060_check_if_an_original_string_exists_given_two_encoded_strings

Class Solution

  • public class Solution
extends Object
    2060 - Check if an Original String Exists Given Two Encoded Strings.

    Hard

    An original string, consisting of lowercase English letters, can be encoded by the following steps:

    • Arbitrarily split it into a sequence of some number of non-empty substrings.
    • Arbitrarily choose some elements (possibly none) of the sequence, and replace each with its length (as a numeric string).
    • Concatenate the sequence as the encoded string.

    For example, one way to encode an original string "abcdefghijklmnop" might be:

    • Split it as a sequence: ["ab", "cdefghijklmn", "o", "p"].
    • Choose the second and third elements to be replaced by their lengths, respectively. The sequence becomes ["ab", "12", "1", "p"].
    • Concatenate the elements of the sequence to get the encoded string: "ab121p".

    Given two encoded strings s1 and s2, consisting of lowercase English letters and digits 1-9 (inclusive), return true if there exists an original string that could be encoded as both s1 and s2. Otherwise, return false.

    Note: The test cases are generated such that the number of consecutive digits in s1 and s2 does not exceed 3.

    Example 1:

    Input: s1 = “internationalization”, s2 = “i18n”

    Output: true

    Explanation: It is possible that “internationalization” was the original string.

    • “internationalization”

      -> Split: [“internationalization”]

      -> Do not replace any element

      -> Concatenate: “internationalization”, which is s1.

    • “internationalization”

      -> Split: [“i”, “nternationalizatio”, “n”]

      -> Replace: [“i”, “18”, “n”]

      -> Concatenate: “i18n”, which is s2

    Example 2:

    Input: s1 = “l123e”, s2 = “44”

    Output: true

    Explanation: It is possible that “leetcode” was the original string.

    • “leetcode”

      -> Split: [“l”, “e”, “et”, “cod”, “e”]

      -> Replace: [“l”, “1”, “2”, “3”, “e”]

      -> Concatenate: “l123e”, which is s1.

    • “leetcode”

      -> Split: [“leet”, “code”]

      -> Replace: [“4”, “4”]

      -> Concatenate: “44”, which is s2.

    Example 3:

    Input: s1 = “a5b”, s2 = “c5b”

    Output: false

    Explanation: It is impossible.

    • The original string encoded as s1 must start with the letter ‘a’.

    • The original string encoded as s2 must start with the letter ‘c’.

    Constraints:

    • 1 <= s1.length, s2.length <= 40
    • s1 and s2 consist of digits 1-9 (inclusive), and lowercase English letters only.
    • The number of consecutive digits in s1 and s2 does not exceed 3.

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • possiblyEquals

        public boolean possiblyEquals​(String s1,
                              String s2)