# GeetCode Hub

Given an encoded string, return its decoded string.

The encoding rule is: `k[encoded_string]`, where the `encoded_string` inside the square brackets is being repeated exactly `k` times. Note that `k` is guaranteed to be a positive integer.

You may assume that the input string is always valid; No extra white spaces, square brackets are well-formed, etc.

Furthermore, you may assume that the original data does not contain any digits and that digits are only for those repeat numbers, `k`. For example, there won't be input like `3a` or `2`.

Example 1:

```Input: s = "3[a]2[bc]"
Output: "aaabcbc"
```

Example 2:

```Input: s = "3[a2[c]]"
Output: "accaccacc"
```

Example 3:

```Input: s = "2[abc]3[cd]ef"
Output: "abcabccdcdcdef"
```

Example 4:

```Input: s = "abc3[cd]xyz"
Output: "abccdcdcdxyz"
```

Constraints:

• `1 <= s.length <= 30`
• `s` consists of lowercase English letters, digits, and square brackets `'[]'`.
• `s` is guaranteed to be a valid input.
• All the integers in `s` are in the range `[1, 300]`.

class Solution { public String decodeString(String s) { } }