You are given a string s
consisting of lowercase English letters, an integer t
representing the number of transformations to perform, and an array nums
of size 26. In one transformation, every character in s
is replaced according to the following rules:
s[i]
with the next nums[s[i] - 'a']
consecutive characters in the alphabet. For example, if s[i] = 'a'
and nums[0] = 3
, the character 'a'
transforms into the next 3 consecutive characters ahead of it, which results in "bcd"
.'z'
. For example, if s[i] = 'y'
and nums[24] = 3
, the character 'y'
transforms into the next 3 consecutive characters ahead of it, which results in "zab"
.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, nums = [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2]
Output: 7
Explanation:
First Transformation (t = 1):
'a'
becomes 'b'
as nums[0] == 1
'b'
becomes 'c'
as nums[1] == 1
'c'
becomes 'd'
as nums[2] == 1
'y'
becomes 'z'
as nums[24] == 1
'y'
becomes 'z'
as nums[24] == 1
"bcdzz"
Second Transformation (t = 2):
'b'
becomes 'c'
as nums[1] == 1
'c'
becomes 'd'
as nums[2] == 1
'd'
becomes 'e'
as nums[3] == 1
'z'
becomes 'ab'
as nums[25] == 2
'z'
becomes 'ab'
as nums[25] == 2
"cdeabab"
Final Length of the string: The string is "cdeabab"
, which has 7 characters.
Example 2:
Input: s = "azbk", t = 1, nums = [2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2]
Output: 8
Explanation:
First Transformation (t = 1):
'a'
becomes 'bc'
as nums[0] == 2
'z'
becomes 'ab'
as nums[25] == 2
'b'
becomes 'cd'
as nums[1] == 2
'k'
becomes 'lm'
as nums[10] == 2
"bcabcdlm"
Final Length of the string: The string is "bcabcdlm"
, which has 8 characters.
Constraints:
1 <= s.length <= 105
s
consists only of lowercase English letters.1 <= t <= 109
nums.length == 26
1 <= nums[i] <= 25
Ashish Pratap Singh