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

You are given a non-negative integer array nums. In one operation, you must:

Choose a positive integer x such that x is less than or equal to the smallest non-zero element in nums.
Subtract x from every positive element in nums.

Return the minimum number of operations to make every element in nums equal to 0.
 
Please complete the following python code precisely:
```python
class Solution:
    def minimumOperations(self, nums: List[int]) -> int:
```