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

You are given a positive integer n, indicating that we initially have an n x n 0-indexed integer matrix mat filled with zeroes.
You are also given a 2D integer array query. For each query[i] = [row1i, col1i, row2i, col2i], you should do the following operation:

Add 1 to every element in the submatrix with the top left corner (row1i, col1i) and the bottom right corner (row2i, col2i). That is, add 1 to mat[x][y] for all row1i <= x <= row2i and col1i <= y <= col2i.

Return the matrix mat after performing every query.
 
Please complete the following python code precisely:
```python
class Solution:
    def rangeAddQueries(self, n: int, queries: List[List[int]]) -> List[List[int]]:
```