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.

**Example 1:**

Input:num = "4321", k = 4Output:"1342"Explanation:The steps to obtain the minimum integer from 4321 with 4 adjacent swaps are shown.

**Example 2:**

Input:num = "100", k = 1Output:"010"Explanation:It's ok for the output to have leading zeros, but the input is guaranteed not to have any leading zeros.

**Example 3:**

Input:num = "36789", k = 1000Output:"36789"Explanation:We can keep the number without any swaps.

**Example 4:**

Input:num = "22", k = 22Output:"22"

**Example 5:**

Input:num = "9438957234785635408", k = 23Output:"0345989723478563548"

**Constraints:**

`1 <= num.length <= 30000`

`num`

contains**digits**only and doesn't have**leading zeros**.`1 <= k <= 10^9`

class Solution {
public String minInteger(String num, int k) {
}
}