java.lang.Object
g3301_3400.s3335_total_characters_in_string_after_transformations_i.Solution

public class Solution extends Object
3335 - Total Characters in String After Transformations I.

Medium

You are given a string s and an integer t, representing the number of transformations to perform. In one transformation , every character in s is replaced according to the following rules:

  • If the character is 'z', replace it with the string "ab".
  • Otherwise, replace it with the next character in the alphabet. For example, 'a' is replaced with 'b', 'b' is replaced with 'c', and so on.

Return the length of the resulting string after exactly t transformations.

Since the answer may be very large, return it modulo 109 + 7.

Example 1:

Input: s = “abcyy”, t = 2

Output: 7

Explanation:

  • First Transformation (t = 1):
    • 'a' becomes 'b'
    • 'b' becomes 'c'
    • 'c' becomes 'd'
    • 'y' becomes 'z'
    • 'y' becomes 'z'
    • String after the first transformation: "bcdzz"
  • Second Transformation (t = 2):
    • 'b' becomes 'c'
    • 'c' becomes 'd'
    • 'd' becomes 'e'
    • 'z' becomes "ab"
    • 'z' becomes "ab"
    • String after the second transformation: "cdeabab"
  • Final Length of the string: The string is "cdeabab", which has 7 characters.

Example 2:

Input: s = “azbk”, t = 1

Output: 5

Explanation:

  • First Transformation (t = 1):
    • 'a' becomes 'b'
    • 'z' becomes "ab"
    • 'b' becomes 'c'
    • 'k' becomes 'l'
    • String after the first transformation: "babcl"
  • Final Length of the string: The string is "babcl", which has 5 characters.

Constraints:

  • 1 <= s.length <= 105
  • s consists only of lowercase English letters.
  • 1 <= t <= 105
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • lengthAfterTransformations

      public int lengthAfterTransformations(String s, int t)