Package g0701_0800.s0753_cracking_the_safe

Class Solution

  • public class Solution
extends Object
    753 - Cracking the Safe\. Hard 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]`. 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. * For example, the correct password is `"345"` and you enter in `"012345"`: * After typing `0`, the most recent `3` digits is `"0"`, which is incorrect. * After typing `1`, the most recent `3` digits is `"01"`, which is incorrect. * After typing `2`, the most recent `3` digits is `"012"`, which is incorrect. * After typing `3`, the most recent `3` digits is `"123"`, which is incorrect. * After typing `4`, the most recent `3` digits is `"234"`, which is incorrect. * After typing `5`, the most recent `3` digits is `"345"`, which is correct and the safe unlocks. Return _any string of **minimum length** that will unlock the safe **at some point** of entering it_. **Example 1:** **Input:** n = 1, k = 2 **Output:** "10" **Explanation:** The password is a single digit, so enter each digit. "01" would also unlock the safe. **Example 2:** **Input:** n = 2, k = 2 **Output:** "01100" **Explanation:** For each possible password: - "00" is typed in starting from the 4th digit. - "01" is typed in starting from the 1st digit. - "10" is typed in starting from the 3rd digit. - "11" is typed in starting from the 2nd digit. Thus "01100" will unlock the safe. "01100", "10011", and "11001" would also unlock the safe. **Constraints:** * `1 <= n <= 4` * `1 <= k <= 10` * 1 <= kn <= 4096

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • crackSafe

        public String crackSafe​(int n,
                        int k)