Decompress Run-Length Encoded List - LeetCode

We are given a list nums of integers representing a list compressed with run-length encoding.

Consider each adjacent pair of elements [freq, val] = [nums[2*i], nums[2*i+1]] (with i >= 0).  For each such pair, there are freq elements with value val concatenated in a sublist. Concatenate all the sublists from left to right to generate the decompressed list.

Return the decompressed list.

"""
1313. Decompress Run-Length Encoded List

We are given a list nums of integers representing a list compressed with run-length encoding.

Consider each adjacent pair of elements
    [freq, val] = [nums[2*i], nums[2*i+1]] (with i >= 0).
For each such pair, there are freq elements with value val concatenated in a sublist.
Concatenate all the sublists from left to right to generate the decompressed list.

Return the decompressed list.

Input: nums = [1,2,3,4]
Output: [2,4,4,4]

Input: nums = [1,1,2,3]
Output: [1,3,3]
"""

nums = [1,1,2,3]

result = []
i = 0

while i < len(nums) - 1:
    freq = nums[i]
    val = nums[i+1]

    j = 0
    while j < freq:
        result.append(val)
        
        j += 1

    i += 2

print(result)