Please solve the programming task below using a self-contained code snippet in a markdown code block.

You are given a string num representing the digits of a very large integer and an integer k. You are allowed to swap any two adjacent digits of the integer at most k times.
Return the minimum integer you can obtain also as a string.
 
Please complete the following python code precisely:
```python
class Solution:
    def minInteger(self, num: str, k: int) -> str:
```