{ "data": { "question": { "questionId": "754", "questionFrontendId": "753", "boundTopicId": null, "title": "Cracking the Safe", "titleSlug": "cracking-the-safe", "content": "

There is a safe protected by a password. The password is a sequence of n digits where each digit can be in the range [0, k - 1].

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The safe has a peculiar way of checking the password. When you enter in a sequence, it checks the most recent n digits that were entered each time you type a digit.

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Return any string of minimum length that will unlock the safe at some point of entering it.

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Example 1:

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\nInput: n = 1, k = 2\nOutput: "10"\nExplanation: The password is a single digit, so enter each digit. "01" would also unlock the safe.\n
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Example 2:

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\nInput: n = 2, k = 2\nOutput: "01100"\nExplanation: For each possible password:\n- "00" is typed in starting from the 4th digit.\n- "01" is typed in starting from the 1st digit.\n- "10" is typed in starting from the 3rd digit.\n- "11" is typed in starting from the 2nd digit.\nThus "01100" will unlock the safe. "01100", "10011", and "11001" would also unlock the safe.\n
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Constraints:

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