An encoded string S
is given. To find and write the decoded
string to a tape, the encoded string is read one character at a time and
the following steps are taken:
d
), the entire current tape is
repeatedly written d-1
more times in total.
Now for some encoded string S
, and an index K
, find and return the
K
-th letter (1 indexed) in the decoded string.
Example 1:
Input: S = "leet2code3", K = 10 Output: "o" Explanation: The decoded string is "leetleetcodeleetleetcodeleetleetcode". The 10th letter in the string is "o".
Example 2:
Input: S = "ha22", K = 5 Output: "h" Explanation: The decoded string is "hahahaha". The 5th letter is "h".
Example 3:
Input: S = "a2345678999999999999999", K = 1 Output: "a" Explanation: The decoded string is "a" repeated 8301530446056247680 times. The 1st letter is "a".
Note:
2 <= S.length <= 100
S
will only contain lowercase letters and digits
2
through 9
.
S
starts with a letter.1 <= K <= 10^9
2^63
letters.