Decoded String at Index
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:
If the character read is a letter, that letter is written onto the tape.
If the character read is a digit (say 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.
Input: S = "leet2code3", K = 10 Output: "o" Explanation: The decoded string is "leetleetcodeleetleetcodeleetleetcode". The 10th letter in the string is "o".
Input: S = "ha22", K = 5 Output: "h" Explanation: The decoded string is "hahahaha". The 5th letter is "h".
Input: S = "a2345678999999999999999", K = 1 Output: "a" Explanation: The decoded string is "a" repeated 8301530446056247680 times. The 1st letter is "a".
- 2 <= S.length <= 100
- S will only contain lowercase letters and digits 2 through 9.
- S starts with a letter.
- 1 <= K <= 10^9
- The decoded string is guaranteed to have less than 2^63 letters.
Credits To: leetcode.com
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- Solution: XXX
Walk Through Testdata
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