- There is a box protected by a password. The password is n digits, where each letter can be one of the first k digits 0, 1, ..., k-1.
- You can keep inputting the password, the password will automatically be matched against the last n digits entered.
- For example, assuming the password is "345", I can open it when I type "012345", but I enter a total of 6 digits.
- Please return any string of minimum length that is guaranteed to open the box after the entire string is inputted.
- Example 1:
- Input: n = 1, k = 2
- Output: "01"
- Note: "10" will be accepted too.
- Example 2:
- Input: n = 2, k = 2
- Output: "00110"
- Note: "01100", "10011", "11001" will be accepted too.
- Note:
- n will be in the range [1, 4].
- k will be in the range [1, 10].
- k^n will be at most
- 4096
- .
- s
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